Absorbent article having improved fecal storage structure

ABSTRACT

An absorbent article including a liquid pervious topsheet, a liquid impervious backsheet joined to at least a portion of the topsheet, an absorbent core disposed between at least a portion of the topsheet and the backsheet, and a waste management element disposed in at least a portion of a crotch region. The waste management element preferably includes an acceptance element having an effective open area of at least about 30 percent and a storage element having a compressive resistance of at least about 70 percent.

This application claims the benefit of U.S. Provisional Application No.60/066,777, filed Nov. 14, 1997.

FIELD OF THE INVENTION

The present invention relates to articles which absorb and/or containbodily exudates, including disposable absorbent articles such asdiapers, adult incontinence products, sanitary napkins and the like.More particularly, the invention relates to disposable absorbentarticles having improved fecal material management properties.

BACKGROUND OF THE INVENTION

The major function of absorbent articles such as diapers and adultincontinence briefs is to prevent body exudates from soiling, wetting,or otherwise contaminating clothing or other articles, such as bedding,that come in contact with the wearer. In recent years, disposablediapers, such as those disclosed in U.S. Pat. No. 3,860,003 issued toKenneth Barclay Buell on Jan. 14, 1975, have become very popular withthe public and have generally replaced durable cloth absorbent articlesbecause of their convenience and reliability. However, despite theeffectiveness of such disposable absorbent articles, body exudates oftenstill leak or are stored in the diaper such that the exudates soiland/or irritate the skin of the wearer.

The undesirable effects of leakage and/or improper containment areespecially evident with regard to fecal matter deposited in the diaper.Feces contained in the diaper can harm the skin of the wearer over timeand feces leaking from the diaper almost invariably presents unpleasant,messy clean-ups. Thus, several attempts have been made to add featuresto diapers such as barriers, pockets, spacers, transverse barriers,apertured topsheets and the like to limit the movement of the materialacross the topsheet and/or to better confine fecal matter in the diaper.However, such attempts have been generally unsuccessful due to theircost and complexity or due to their limited success in reducing thenegative effects of the feces.

Although the present invention may be adapted to provide improvedmanagement of any bodily exudates, the embodiments described hereinbeloware especially suitable for controlling viscous fluid bodily wastes.Such viscous fluid bodily wastes include soft or runny feces, and thelike, which are generally more viscous than urine but less viscous thannormal solid adult feces. Viscous fluid bodily wastes are difficult toabsorb and/or contain in conventional absorbent structures because thenormal capillary forces which acquire and transport extremely lowviscosity fluids like urine are insufficient to move such viscous fluidbodily wastes. Thus, the viscous fluid body wastes often remain on thetopsheet of the article where they are generally unrestricted inmovement and accessible to and in contact with the wearer's skin.Further, the fluid characteristics of the waste permit it to flow acrossthe topsheet and sometimes leak out of the article. Accordingly, thespecial characteristics of viscous fluid bodily wastes need to beaddressed by unique storage structures.

Accordingly, it would be desirable to provide an absorbent structurewith improved feces management properties. Further, it would beadvantageous to provide an economical disposable absorbent article withthe ability to minimize the negative effects of feces or other viscousfluid bodily waste on the wearer or the caregiver. It would also beadvantageous to provide an absorbent article which is specificallydesigned to accept viscous fluid bodily wastes such as fecal material,especially relatively lower viscosity fecal material such as soft orrunny feces. Also, it would be desirable to provide an absorbent articlehaving sufficient effective capacity and retention capability to storefeces deposited therein safely and cleanly away from the wearer's skinand/or clothing throughout the expected time of use.

SUMMARY OF THE INVENTION

In order to better manage viscous fluid bodily wastes, the presentinvention provides an absorbent article having a first waist region, asecond waist region opposed to the first waist region and a crotchregion disposed between the first waist region and the second waistregion. The absorbent article comprises a liquid pervious topsheet, aliquid impervious backsheet joined to at least a portion of thetopsheet, an absorbent core disposed between at least a portion of thetopsheet and the backsheet, and a waste management element disposed inat least a portion of the crotch region. The waste management elementincludes an acceptance element having an effective open area of at leastabout 30% and an Acceptance Under Pressure value of greater than about0.70 grams of a viscous fluid bodily waste per square inch of theacceptance element per milliJoule of energy input. The waste managementelement further includes a storage element disposed between at least aportion of the acceptance element and the backsheet. The storage elementhas a compressive resistance of at least about 70% and a Storage UnderPressure value of greater than about 0.70 grams of the viscous fluidbodily waste per square inch of the storage element. The effective openarea ensures that viscous fluid bodily wastes are quickly andefficiently imbibed by the article. Further, the improved compressiveresistance may reduce the likelihood that normal wearing forces willrelease the waste from the storage element once the waste is imbibed bythe article. Accordingly, the absorbent article of the present inventionmay reduce the likelihood of harm to the wearer's skin and/or theinconvenience to the caregiver normally associated with bowel movements,and especially runny feces.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims particularly pointing outand distinctly claiming the subject matter which is regarded as thepresent invention, it is believed that the description will be betterunderstood from the following descriptions which are taken inconjunction with the accompanying drawings in which like designationsare used to designate substantially identical elements.

FIG. 1 is a plan view of an absorbent article embodiment of the presentinvention having portions cut away to reveal the underlying structure,the body-facing surface of the diaper facing the viewer.

FIG. 2 is a schematic front and cutaway view of an apparatus which maybe used to measure Acceptance Under Pressure and Storage Under Pressurecharacteristics of structures.

FIG. 3 is a schematic side view of an apparatus which may be used tomeasure retention and Immobilization Under Compressed Inversioncharacteristics of structures.

FIG. 4 is a plan view of a piece of the apparatus shown in FIG. 3.

FIG. 5 is a plan view of one embodiment of the present invention havingportions cut away to reveal the underlying structure, the body facingsurface of the diaper facing the viewer.

FIG. 6 is a cross sectional view of the diaper of FIG. 5 taken through6—6.

FIG. 6A is a cross sectional view of an alternative embodiment of thepresent invention.

FIG. 7 is a plan view of one embodiment of the present invention havingportions cut away to reveal the underlying structure, the body facingsurface of the diaper facing the viewer.

FIG. 8 is a plan and cutaway view of an alternative embodiment of thepresent invention.

FIG. 9 is a 3-dimensional graphical representation of the relationshipbetween Acceptance Under Pressure, Storage Under Pressure andImmobilization Under Compressed Inversion values of exemplarystructures.

FIG. 10 is a 3-dimensional graphical representation of the relationshipbetween Acceptance Under Pressure, Storage Under Pressure and retentionvalues of exemplary structures.

FIG. 11 is a 2-dimensional graphical representation of the relationshipbetween Acceptance Under Pressure and Storage Under Pressure values ofexemplary structures.

FIG. 12 is a 2-dimensional graphical representation of the relationshipbetween retention and Immobilization Under Compressed Inversion valuesof exemplary structures.

FIG. 13 is a 2-dimensional graphical representation of the relationshipbetween Immobilization Under Compressed Inversion and Storage UnderPressure values of exemplary structures.

FIG. 14 is a 2-dimensional graphical representation of the relationshipbetween Storage Under Pressure and Receptivity Under Pressure values ofexemplary structures.

FIG. 15 is a 2-dimensional graphical representation of the relationshipbetween Storage Under Pressure and Compressive Resistance values ofexemplary structures.

FIG. 16 is a 2-dimensional graphical representation of the relationshipbetween Immobilization Under Compressed Inversion and CompressiveResistance values of exemplary structures.

FIG. 17 is a 2-dimensional graphical representation of the relationshipbetween Storage Under Pressure and Void Volume values of exemplarystructures.

FIG. 18 is a 2-dimensional graphical representation of the relationshipbetween Immobilization Under Compressed Inversion and CompressiveResistance values of exemplary structures.

FIG. 19 is a 2-dimensional graphical representation of the relationshipbetween Immobilization Under Compressed Inversion values of exemplarystructures and the Effective Open Area of an associated acceptanceelement.

FIG. 20 is a 2-dimensional graphical representation of the relationshipbetween Storage Under Pressure values of exemplary structures and theEffective Open Area of an associated acceptance element.

FIG. 21 is a 2-dimensional graphical representation of the relationshipbetween Acceptance Under Pressure values of exemplary structures and theEffective Open Area of an associated acceptance element.

FIG. 22 is a 2-dimensional graphical representation of the relationshipbetween Storage Under Pressure values of exemplary structures and theEffective Open Area of an associated acceptance element.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the term “absorbent article” refers to devices whichabsorb and contain body exudates, and more specifically, refers todevices which are placed against or in proximity to the body of thewearer to absorb and contain the various exudates discharged from thebody. The term “disposable” is used herein to describe absorbentarticles which generally are not intended to be laundered or otherwiserestored or reused as an absorbent article (i.e., they are intended tobe discarded after a single use and, preferably, to be recycled,composted or otherwise disposed of in an environmentally compatiblemanner). (As used herein, the term “disposed” is used to mean that anelement(s) of the diaper is formed (joined and positioned) in aparticular place or position as a unitary structure with other elementsof the diaper or as a separate element joined to another element of thediaper. As used herein, the term “joined” encompasses configurationswhereby an element is directly secured to another element by affixingthe element directly to the other element, and configurations whereby anelement is indirectly secured to another element by affixing the elementto intermediate member(s) which in turn are affixed to the otherelement.) A “unitary” absorbent article refers to absorbent articleswhich are formed of separate parts united together to form a coordinatedentity so that they do not require separate manipulative parts like aseparate holder and liner. A preferred embodiment of an absorbentarticle of the present invention is the unitary disposable absorbentarticle, diaper 20, shown in FIG. 1. As used herein, the term “diaper”refers to an absorbent article generally worn by infants and incontinentpersons about the lower torso. The present invention is also applicableto other absorbent articles such as incontinence briefs, incontinenceundergarments, absorbent inserts, diaper holders and liners, femininehygiene garments, wipes, mops, bandages and the like.

FIG. 1 is a plan view of the diaper 20 of the present invention in aflat-out, state with portions of the structure being cut-away to moreclearly show the construction of the diaper 20. The portion of thediaper 20 which faces the wearer is oriented towards the viewer. Asshown in FIG. 1, the diaper 20 preferably comprises a liquid pervioustopsheet 24; a liquid impervious backsheet 26; an absorbent core 28,which is preferably positioned between at least a portion of thetopsheet 24 and the backsheet 26; side panels 30; elasticized leg cuffs32; an elastic waist feature 34; and a fastening system generallydesignated 40. Diaper 20 is shown in FIG. 1 to have a first waist region36, a second waist region 38 opposed to the first waist region 36 and acrotch region 37 located between the first waist region and the secondwaist region. The periphery of the diaper 20 is defined by the outeredges of the diaper 20 in which the longitudinal edges 50 run generallyparallel to the longitudinal centerline 100 of the diaper 20 and the endedges 52 run between the longitudinal edges 50 generally parallel to thelateral centerline 110 of the diaper 20.

The chassis 22 of the diaper 20 comprises the main body of the diaper20. The chassis 22 comprises at least a portion of the absorbent core 28and preferably an outer covering layer including the topsheet 24 and thebacksheet 26. If the absorbent article comprises a separate holder and aliner, the chassis 22 generally comprises the holder and the liner. (Forexample, the holder may comprise one or more layers of material to formthe outer cover of the article and the liner may comprise an absorbentassembly including a topsheet, a backsheet, and an absorbent core. Insuch cases, the holder and/or the liner may include a fastening elementwhich is used to hold the liner in place throughout the time of use.)For unitary absorbent articles, the chassis 22 comprises the mainstructure of the diaper with other features added to form the compositediaper structure. While the topsheet 24, the backsheet 26, and theabsorbent core 26 may be assembled in a variety of well knownconfigurations, preferred diaper configurations are described generallyin U.S. Pat. No. 3,860,003 entitled “Contractible Side Portions forDisposable Diaper” which issued to Kenneth B. Buell on Jan. 14, 1975;U.S. Pat. No. 5,151,092 issued to Buell on Sep. 9, 1992; and U.S. Pat.No. 5,221,274 issued to Buell on Jun. 22, 1993; and U.S. Pat. No.5,554,145 entitled “Absorbent Article With Multiple Zone StructuralElastic-Like Film Web Extensible Waist Feature” which issued to Roe etal. on Sep. 10, 1996; U.S. Pat. No. 5,569,234 entitled “DisposablePull-On Pant” which issued to Buell et al. on Oct. 29, 1996; U.S. Pat.No. 5,580,411 entitled “Zero Scrap Method For Manufacturing Side PanelsFor Absorbent Articles” which issued to Nease et al. on Dec. 3, 1996;and U.S. patent application Ser. No. 08/915,471 entitled “AbsorbentArticle With Multi-Directional Extensible Side Panels” filed Aug. 20,1997 in the name of Robles et al.; each of which is incorporated hereinby reference.

The backsheet 26 is generally that portion of the diaper 20 positionedadjacent the garment facing surface of the absorbent core 28 whichprevents the exudates absorbed and contained therein from soilingarticles which may contact the diaper 20, such as bedsheets andundergarments. In preferred embodiments, the backsheet 26 is imperviousto liquids (e.g., urine) and comprises a thin plastic film such as athermoplastic film having a thickness of about 0.012 mm (0.5 mil) toabout 0.051 mm (2.0 mils). Suitable backsheet films include thosemanufactured by Tredegar Industries Inc. of Terre Haute, Ind. and soldunder the trade names X15306, X10962 and X10964. Other suitablebacksheet materials may include breathable materials which permit vaporsto escape from the diaper 20 while still preventing exudates frompassing through the backsheet 26. Exemplary breathable materials mayinclude materials such as woven webs, nonwoven webs, composite materialssuch as film-coated nonwoven webs, and microporous films such asmanufactured by Mitsui Toatsu Co., of Japan under the designation ESPOIRNO and by EXXON Chemical Co., of Bay City, Tex., under the designationEXXAIRE. Suitable breathable composite materials comprising polymerblends are available from Clopay Corporation, Cincinnati, Ohio under thename HYTREL blend P18-3097. Such breathable composite materials aredescribed in greater detail in PCT Application No. WO 95/16746,published on Jun. 22, 1995 in the name of E. I. DuPont and copendingU.S. patent application Ser. No. 08/744,487, filed on Nov. 6, 1996 inthe name of Curro. Other breathable backsheets including nonwoven websand apertured formed films are described in U.S. Pat. No. 5,571,096issued to Dobrin et al. on Nov. 5, 1996. Each of these references ishereby incorporated by reference herein.

The backsheet 26, or any portion thereof, may be elastically extensiblein one or more directions. In one embodiment, the backsheet 26 maycomprise a structural elastic-like film (“SELF”) web. A structuralelastic-like film web is an extensible material that exhibits anelastic-like behavior in the direction of elongation without the use ofadded elastic materials. The SELF web includes a strainable networkhaving at least two contiguous, distinct, and dissimilar regions.Preferably, one of the regions is configured so that it will exhibitresistive forces in response to an applied axial elongation in adirection parallel to the predetermined axis before a substantialportion of the other region develops significant resistive forces to theapplied elongation. At least one of the regions has a surface-pathlengthwhich is greater than that of the other region as measured substantiallyparallel to the predetermined axis while the material is in anuntensioned condition. The region exhibiting the longersurface-pathlength includes one or more deformations which extend beyondthe plane of the other region. The SELF web exhibits at least twosignificantly different stages of controlled resistive force toelongation along at least one predetermined axis when subjected to anapplied elongation in a direction parallel to the predetermined axis.The SELF web exhibits first resistive forces to the applied elongationuntil the elongation of the web is sufficient to cause a substantialportion of the region having the longer surface-pathlength to enter theplane of applied elongation, whereupon the SELF web exhibits secondresistive forces to further elongation. The total resistive forces toelongation are higher than the first resistive forces to elongationprovided by the first region. SELF webs suitable for the presentinvention are more completely described in U.S. Pat. No. 5,518,801entitled Web Materials Exhibiting Elastic-Like Behavior, which issued toChappell, et, al. on May 21, 1996, which is incorporated herein byreference. In alternate embodiments, the backsheet 26 may compriseelastomeric films, foams, strands, or combinations of by these or othersuitable materials with nonwovens or synthetic films.

The backsheet 26 may be joined to the topsheet 24, the absorbent core 28or any other element of the diaper 20 by any attachment means known inthe art. For example, the attachment means may include a uniformcontinuous layer of adhesive, a patterned layer of adhesive, or an arrayof separate lines, spirals, or spots of adhesive. One preferredattachment means comprises an open pattern network of filaments ofadhesive as disclosed in U.S. Pat. No. 4,573,986 entitled “DisposableWaste-Containment Garment”, which issued to Minetola et al. on Mar. 4,1986. Other suitable attachment means include several lines of adhesivefilaments which are swirled into a spiral pattern, as is illustrated bythe apparatus and methods shown in U.S. Pat. No. 3,911,173 issued toSprague, Jr. on Oct. 7, 1975; U.S. Pat. No. 4,785,996 issued to Ziecker,et al. on Nov. 22, 1978; and U.S. Pat. No. 4,842,666 issued to Wereniczon Jun. 27, 1989. Each of these patents are incorporated herein byreference. Adhesives which have been found to be satisfactory aremanufactured by H. B. Fuller Company of St. Paul, Minn. and marketed asHL-1620 and HL-1358-XZP. Alternatively, the attachment means maycomprise heat bonds, pressure bonds, ultrasonic bonds, dynamicmechanical bonds, or any other suitable attachment means or combinationsof these attachment means as are known in the art.

The topsheet 24 is preferably positioned adjacent the body surface 47 ofthe absorbent core 28 and may be joined thereto and/or to the backsheet26 by any attachment means known in the art. Suitable attachment meansare described above with respect to means for joining the backsheet 26to other elements of the diaper 20. In one preferred embodiment of thepresent invention, the topsheet 24 and the backsheet 26 are joineddirectly to each other in some locations and are indirectly joinedtogether in other locations by directly joining them to other elementsof the diaper 20.

The topsheet 24 is preferably compliant, soft feeling, andnon-irritating to the wearer's skin. Further, at least a portion of thetopsheet 24 is liquid pervious, permitting liquids to readily penetratethrough its thickness. A suitable topsheet 24 may be manufactured from awide range of materials, such as porous foams; reticulated foams;apertured plastic films; or woven or nonwoven webs of natural fibers(e.g., wood or cotton fibers), synthetic fibers (e.g., polyester orpolypropylene fibers), or a combination of natural and synthetic fibers.If the absorbent assemblies include fibers, the fibers may be spunbond,carded, wet-laid, meltblown, hydroentangled, or otherwise processed asis known in the art. One suitable topsheet 24 comprising a web of staplelength polypropylene fibers is manufactured by Veratec, Inc., a Divisionof International Paper Company, of Walpole, Mass. under the designationP-8.

Suitable formed film topsheets are described in U.S. Pat. No. 3,929,135,entitled “Absorptive Structures Having Tapered Capillaries”, whichissued to Thompson on Dec. 30, 1975; U.S. Pat. No. 4,324,246 entitled“Disposable Absorbent Article Having A Stain Resistant Topsheet”, whichissued to Mullane, et al. on Apr. 13, 1982; U.S. Pat. No. 4,342,314entitled “Resilient Plastic Web Exhibiting Fiber-Like Properties”, whichissued to Radel, et al. on Aug. 3, 1982; U.S. Pat. No. 4,463,045entitled “Macroscopically Expanded Three-Dimensional Plastic WebExhibiting Non-Glossy Visible Surface and Cloth-Like TactileImpression”, which issued to Ahr, et al. on Jul. 31, 1984; and U.S. Pat.No. 5,006,394 “Multilayer Polymeric Film” issued to Baird on Apr. 9,1991. Other suitable topsheets 30 are made in accordance with U.S. Pat.Nos. 4,609,518 and 4,629,643 which issued to Curro et al. on Sep. 2,1986 and Dec. 16, 1986, respectively, and both of which are incorporatedherein by reference. Such formed films are available from The Procter &Gamble Company of Cincinnati, Ohio as DRI-WEAVE and from TredegarCorporation of Terre Haute, Ind. as CLIFF-T.

Preferably, the topsheet 24 is made of a hydrophobic material or istreated to be hydrophobic in order to isolate the wearer's skin fromliquids contained in the absorbent core 28. If the topsheet 24 is madeof a hydrophobic material, preferably at least the upper surface of thetopsheet 24 is treated to be hydrophilic so that liquids will transferthrough the topsheet more rapidly. This diminishes the likelihood thatbody exudates will flow off the topsheet 24 rather than being drawnthrough the topsheet 24 and being absorbed by the absorbent core 28. Thetopsheet 24 can be rendered hydrophilic by treating it with a surfactantor by incorporating a surfactant into the topsheet. Suitable methods fortreating the topsheet 24 with a surfactant include spraying the topsheet24 material with the surfactant and immersing the material into thesurfactant. A more detailed discussion of such a treatment andhydrophilicity is contained in U.S. Pat. No. 4,988,344 entitled“Absorbent Articles with Multiple Layer Absorbent Layers” issued toReising, et al. on Jan. 29, 1991 and U.S. Pat. No. 4,988,345 entitled“Absorbent Articles with Rapid Acquiring Absorbent Cores” issued toReising on Jan. 29, 1991. A more detailed discussion of some suitablemethods for incorporating surfactant in the topsheet can be found inU.S. Statutory Invention Registration No. H1670, published on Jul. 1,1997 in the names of Aziz et al. Each of these references is herebyincorporated by reference herein. Alternatively, the topsheet 24 mayinclude an apertured web or film which is hydrophobic. This may beaccomplished eliminating the hydrophilizing treatment step from theproduction process and/or applying a hydrophobic treatment to thetopsheet 24, such as a polytetraflouroethylene compound like SCOTCHGUARDor a hydrophobic lotion composition, as described below. In suchembodiments, it is preferred that the apertures be large enough to allowthe penetration of aqueous fluids like urine without significantresistance.

Any portion of the topsheet 24 may be coated with a lotion as is knownin the art. Examples of suitable lotions include those described in U.S.Pat. No. 5,607,760 entitled “Disposable Absorbent Article Having ALotioned Topsheet Containing an Emollient and a Polyol PolyesterImmobilizing Agent” which issued to Roe on Mar. 4, 1997; U.S. Pat. No.5,609,587 entitled “Diaper Having A Lotion Topsheet Comprising A LiquidPolyol Polyester Emollient And An Immobilizing Agent” which issued toRoe on Mar. 11, 1997; U.S. Pat. No. 5,635,191 entitled “Diaper Having ALotioned Topsheet Containing A Polysiloxane Emollient” which issued toRoe et al. on Jun. 3, 1997; and U.S. Pat. No. 5,643,588 entitled “DiaperHaving A Lotioned Topsheet” which issued to Roe et al. on Jul. 1, 1997.The lotion may function alone or in combination with another agent asthe hydrophobizing treatment described above. The topsheet may alsoinclude or be treated with antibacterial agents, some examples of whichare disclosed in PCT Publication No. WO 95/24173 entitled “AbsorbentArticles Containing Antibacterial Agents in the Topsheet For OdorControl” which was published on Sep. 14, 1995 in the name of TheresaJohnson. Further, the topsheet 24, the backsheet 26 or any portion ofthe topsheet or backsheet may be embossed and/or matte finished toprovide a more cloth like appearance.

The absorbent core 28 may comprise any absorbent material which isgenerally compressible, conformable, non-irritating to the wearer'sskin, and capable of absorbing and retaining liquids such as urine andother certain body exudates. The absorbent core 28 may be manufacturedin a wide variety of sizes and shapes (e.g., rectangular, hourglass,“T”-shaped, asymmetric, etc.) and may comprise a wide variety ofliquid-absorbent materials commonly used in disposable diapers and otherabsorbent articles such as comminuted wood pulp, which is generallyreferred to as airfelt. Examples of other suitable absorbent materialsinclude creped cellulose wadding; meltblown polymers, including coform;chemically stiffened, modified or cross-linked cellulosic fibers;tissue, including tissue wraps and tissue laminates; absorbent foams;absorbent sponges; superabsorbent polymers; absorbent gelling materials;or any other known absorbent material or combinations of materials.

The configuration and construction of the absorbent core 28 may also bevaried (e.g., the absorbent core(s) or other absorbent structure(s) mayhave varying caliper zones, a hydrophilic gradient, a superabsorbentgradient, or lower average density and lower average basis weightacquisition zones; or may comprise one or more layers or structures).However, the total absorbent capacity of the absorbent core 28 should becompatible with the design loading and the intended use of the diaper20.

Exemplary absorbent structures for use as the absorbent assemblies aredescribed in U.S. Pat. No. 4,610,678 entitled “High-Density AbsorbentStructures” issued to Weisman et al. on Sep. 9, 1986; U.S. Pat. No.4,673,402 entitled “Absorbent Articles With Dual-Layered Cores” issuedto Weisman et al. on Jun. 16, 1987; U.S. Pat. No. 4,834,735, entitled“High Density Absorbent Members Having Lower Density and Lower BasisWeight Acquisition Zones”, issued to Alemany et al. on May 30, 1989;U.S. Pat. No. 4,888,231 entitled “Absorbent Core Having A Dusting Layer”issued to Angstadt on Dec. 19, 1989; U.S. Pat. No. 5,137,537 entitled“Absorbent Structure Containing Individualized, Polycarboxylic AcidCrosslinked Wood Pulp Cellulose Fibers” which issued to Herron et al. onAug. 11, 1992; U.S. Pat. No. 5,147,345 entitled “High EfficiencyAbsorbent Articles For Incontinence Management” issued to Young et al.on Sep. 15, 1992; U.S. Pat. No. 5,342,338 entitled “Disposable AbsorbentArticle For Low-Viscosity Fecal Material” issued to Roe on Aug. 30,1994; U.S. Pat. No. 5,260,345 entitled “Absorbent Foam Materials ForAqueous Body Fluids and Absorbent Articles Containing Such Materials”issued to DesMarais et al. on Nov. 9, 1993; U.S. Pat. No. 5,387,207entitled “Thin-Until-Wet Absorbent Foam Materials For Aqueous BodyFluids And Process For Making Same” issued to Dyer et al. on Feb. 7,1995; and U.S. Pat. No. 5,650,222 entitled “Absorbent Foam Materials ForAqueous Fluids Made From high Internal Phase Emulsions Having Very HighWater-To-Oil Ratios” issued to DesMarais et al. on Jul. 22, 1997. Eachof these patents is incorporated herein by reference.

The diaper 20 may also comprise at least one elastic waist feature 34that helps to provide improved fit and containment. The elastic waistfeature 34 is generally intended to elastically expand and contract todynamically fit the wearer's waist. The elastic waist feature 34preferably extends at least longitudinally outwardly from at least onewaist edge 62 of the absorbent core 28 and generally forms at least aportion of the end edge 52 of the diaper 20. Disposable diapers areoften constructed so as to have two elastic waist features, onepositioned in the first waist region 36 and one positioned in the secondwaist region 38. Further, while the elastic waist feature 34 or any ofits constituent elements may comprise one or more separate elementsaffixed to the diaper 20, the elastic waist feature 34 may beconstructed as an extension of other elements of the diaper 20, such asthe backsheet 26, the topsheet 24, or both the backsheet 26 and thetopsheet 24.

The elastic waist feature 34 may be constructed in a number of differentconfigurations including those described in U.S. Pat. No. 4,515,595issued to Kievit et al. on May 7, 1985; U.S. Pat. No. 4,710,189 issuedto Lash on Dec. 1, 1987; U.S. Pat. No. 5,151,092 issued to Buell on Sep.9, 1992; and U.S. Pat. No. 5,221,274 issued to Buell on Jun. 22, 1993.Other suitable waist configurations may include waistcap features suchas those described in U.S. Pat. No. 5,026,364 issued to Robertson onJun. 25, 1991 and U.S. Pat. No. 4,816,025 issued to Foreman on Mar. 28,1989. All of the above mentioned references are incorporated herein byreference.

The diaper 20 may also include a fastening system 40. The fasteningsystem 40 preferably maintains the first waist region 36 and the secondwaist region 38 in an overlapping configuration so as to provide lateraltensions about the circumference of the diaper 20 to hold the diaper 20on the wearer. The fastening system 40 preferably comprises tape tabsand/or hook and loop fastening components, although any other knownfastening means are generally acceptable. Some exemplary fasteningsystems are disclosed in U.S. Pat. No. 3,848,594 entitled “TapeFastening System for Disposable Diaper” issued to Buell on Nov. 19,1974; U.S. Pat. B1 4,662,875 entitled “Absorbent Article” issued toHirotsu et al. on May 5, 1987; U.S. Pat. No. 4,846,815 entitled“Disposable Diaper Having An Improved Fastening Device” issued toScripps on Jul. 11, 1989; U.S. Pat. No. 4,894,060 entitled “DisposableDiaper With Improved Hook Fastener Portion” issued to Nestegard on Jan.16, 1990; U.S. Pat. No. 4,946,527 entitled “Pressure-Sensitive AdhesiveFastener And Method of Making Same” issued to Battrell on Aug. 7, 1990;and the herein before referenced U.S. Pat. No. 5,151,092 issued to Buellon Sep. 9, 1992; and U.S. Pat. No. 5,221,274 issued to Buell on Jun. 22,1993. The fastening system may also provide a means for holding thearticle in a disposal configuration as disclosed in U.S. Pat. No.4,963,140 issued to Robertson et al. on Oct. 16, 1990. Each of thesepatents is incorporated herein by reference. In alternative embodiments,opposing sides of the garment may be seamed or welded to form a pant.This allows the article to be used as a pull-on type diaper, such as atraining pant.

The diaper 20 may also comprise side panels 30. The side panels 30 maybe elastic or extensible to provide a more comfortable and contouringfit by initially conformably fitting the diaper 20 to the wearer andsustaining this fit throughout the time of wear well past when thediaper 20 has been loaded with exudates since the elasticized sidepanels 30 allow the sides of the diaper 20 to expand and contract. Theside panels 30 may also provide more effective application of the diaper20 because even if the diaper pulls one elasticized side panel 30farther than the other during application, the diaper 20 will“self-adjust” during wear.

While the diaper 20 of the present invention preferably has the sidepanels 30 disposed in the second waist region 38, the diaper 20 may beprovided with side panels 30 disposed in the first waist region 36 or inboth the first waist region 36 and the second waist region 38. The sidepanels 30 may be constructed in any suitable configurations. Examples ofdiapers with elasticized side panels are disclosed in U.S. Pat. No.4,857,067, entitled “Disposable Diaper Having Shirred Ears” issued toWood, et al. on Aug. 15, 1989; U.S. Pat. No. 4,381,781 issued toSciaraffa, et al. on May 3, 1983; U.S. Pat. No. 4,938,753 issued to VanGompel, et al. on Jul. 3, 1990; the herein before referenced U.S. Pat.No. 5,151,092 issued to Buell on Sep. 9, 1992; and U.S. Pat. No.5,221,274 issued to Buell on Jun. 22, 1993; U.S. Pat. No. 5,669,897issued to LaVon, et al. on Sep. 23, 1997 entitled “Absorbent ArticlesProviding Sustained Dynamic Fit”; U.S. patent application Ser. No.08/155,048 entitled “Absorbent Article With Multi-Directional ExtensibleSide Panels” filed Nov. 19, 1993 in the names of Robles, et al.; each ofwhich is incorporated herein by reference.

The diaper 20 preferably further includes leg cuffs 32 which provideimproved containment of liquids and other body exudates. Leg cuffs mayalso be referred to as leg bands, side flaps, barrier cuffs, or elasticcuffs. U.S. Pat. No. 3,860,003 describes a disposable diaper whichprovides a contractible leg opening having a side flap and one or moreelastic members to provide an elasticized leg cuff (a gasketing cuff).U.S. Pat. Nos. 4,808,178 and 4,909,803 issued to Aziz et al. on Feb. 28,1989 and Mar. 20, 1990, respectively, describe disposable diapers having“stand-up” elasticized flaps (barrier cuffs) which improve thecontainment of the leg regions. U.S. Pat. Nos. 4,695,278 and 4,795,454issued to Lawson on Sep. 22, 1987 and to Dragoo on Jan. 3, 1989,respectively, describe disposable diapers having dual cuffs, includinggasketing cuffs and barrier cuffs. In some embodiments, it may bedesirable to treat all or a portion of the leg cuffs with a lotion, asdescribed above.

Embodiments of the present invention may also include pockets forreceiving and containing waste, spacers which provide voids for waste,barriers for limiting the movement of waste in the article, compartmentsor voids which accept and contain waste materials deposited in thediaper, and the like, or any combinations thereof. Examples of pocketsand spacers for use in absorbent products are described in U.S. Pat. No.5,514,121 issued to Roe et al. on May 7, 1996, entitled “Diaper HavingExpulsive Spacer”; U.S. Pat. No. 5,171,236 issued to Dreier et al onDec. 15, 1992, entitled “Disposable Absorbent Article Having CoreSpacers”; U.S. Pat. No. 5,397,318 issued to Dreier on Mar. 14, 1995,entitled “Absorbent Article Having A Pocket Cuff”; U.S. Pat. No.5,540,671 issued to Dreier on Jul. 30, 1996, entitled “Absorbent ArticleHaving A Pocket Cuff With An Apex”; and PCT Application WO 93/25172published Dec. 3, 1993, entitled “Spacers For Use In Hygienic AbsorbentArticles And Disposable Absorbent Articles Having Such Spacer”; and U.S.Pat. No. 5,306,266, entitled “Flexible Spacers For Use In DisposableAbsorbent Articles”, issued to Freeland on Apr. 26, 1994. Examples ofcompartments or voids are disclosed in U.S. Pat. No. 4,968,312, entitled“Disposable Fecal Compartmenting Diaper”, issued to Khan on Nov. 6,1990; U.S. Pat. No. 4,990,147, entitled “Absorbent Article With ElasticLiner For Waste Material Isolation”, issued to Freeland on Feb. 5, 1991;U.S. Pat. No. 5,062,840, entitled “Disposable Diapers”, issued to Holtet al on Nov. 5, 1991; and U.S. Pat. No. 5,269,775 entitled “TrisectionTopsheets For Disposable Absorbent Articles And Disposable AbsorbentArticles Having Such Trisection Topsheets”, issued to Freeland et al onDec. 14, 1993. Examples of suitable transverse barriers are described inU.S. Pat. No. 5,554,142 entitled “Absorbent Article Having MultipleEffective Height Transverse Partition” issued Sep. 10, 1996 in the nameof Dreier et al.; PCT Patent WO 94/14395 entitled “Absorbent ArticleHaving An Upstanding Transverse Partition” published Jul. 7, 1994 in thename of Freeland, et al.; and U.S. Pat. No. 5,653,703 Absorbent ArticleHaving Angular Upstanding Transverse Partition, issued Aug. 5, 1997 toRoe, et al. All of the above-cited references are hereby incorporated byreference herein.

In addition to or in place of the voids, pockets and barriers, describedabove, embodiments of the present invention preferably include a wastemanagement element 120 capable of effectively and efficiently accepting,storing and/or immobilizing viscous fluid bodily waste, such as runnyfeces or menses. The waste management element 120 can be locatedanywhere in the article, including the crotch region or either waistregion, or may be associated with or be included in any structure orelement such as the core 28, a leg cuff, etc. In preferred embodiments,the waste management element 120 is located in the region of the articlethat is near the wearer's perianal region when worn. This helps ensurethat any waste discharged is deposited on or near the waste managementelement 120.

As used herein, the term “viscous fluid bodily waste” or “VFBW”generally refers to any waste discarded from the body which has aviscosity of greater than about 10 cP and less than about 2×10⁵ cP at ashear rate of one 1/sec, (at about 35 degrees C.), more particularlybetween about 10³ cP and 10⁵ cP at a one 1/sec shear rate, in acontrolled stress rheometry test using parallel plates on a controlledstress rheometer. (For reference, water is at 1.0 cP at 20 degrees C.and Jif Creamy peanut butter (available from the Procter & Gamble Co.,Cinti., Ohio) is approximately 4×10⁵ cP at 25 degrees C. at this sameshear rate). The method for determining viscosity, as used herein, isdescribed in detail in the Test Method section below.

As used herein, the term “accept” or “acceptance” refers to thepenetration of a structure by materials deposited thereon. Specifically,the term “accept” refers to the penetration of a structure by a fluidwhen subjected to the conditions set forth in the Acceptance UnderPressure Test, described in the Test Methods Section. Penetration isdefined by the passage of materials through the surface of the structureupon which the material was deposited. Penetration of nonuniformstructures can be defined as the passage of a material through a planedefining the surface upon which the material was deposited. AcceptanceUnder Pressure, or “acceptance” is measured as the amount of materialthat penetrates the surface of the structure per unit area per unit workdone. “Work” is an energy term referring to the application of forcethrough a distance. Thus, structures or elements that more readilyaccept viscous fluid bodily wastes require less energy to be expendedper unit mass of the viscous fluid bodily waste accepted by thestructure. An alternative performance parameter in describing thepenetration of a structure by VFBW is “receptivity”. As used herein, theterm “receptivity” refers to the penetration of a structure by a fluidper unit area per unit of power when subjected to the conditions setforth in the Receptivity Under Pressure test, described in the TestMethods section. Receptivity Under Pressure, or “receptivity” ismeasured as the amount of material that penetrates the surface of thestructure per unit area per unit of power. “Power” is a term referringto amount of work done as a function of time (i.e., the rate at whichwork is done).

In preferred embodiments, the absorbent article of the present inventionshould include a waste management element 120 having an Acceptance UnderPressure of greater than about 0.5 g of viscous fluid bodily waste persquare inch of the waste management element 120 per mJ (milliJoule)energy input. More preferably, the waste management element 120 shouldhave an Acceptance Under Pressure of greater than about 0.6 g/in²/mJ ofviscous fluid bodily waste. Even more preferably, the waste managementelement 120 should have an Acceptance Under Pressure of greater thanabout 0.8 g/in²/mJ, and most preferably greater than about 1.0 g/in²/mJof viscous fluid bodily waste. Generally, Acceptance Under Pressurevalues between at least about 0.6 g/in²/mJ and about 10.0 g/in²/mJ, andbetween about 0.8 g/in²/mJ and about 10.0 g/in²/mJ have been found to beacceptable. Alternatively, the waste acceptance element 120 should havea Receptivity Under Pressure of at least about 1.5 grams of viscousfluid bodily waste per square inch of the waste management element 120per milliwatt (mW) of power, more preferably greater than about 3.0g/in²/mW, even more preferably greater than about 5.0 g/in²/mW, mostpreferably greater than about 10.0 g/in²/mW. Generally, the ReceptivityUnder Pressure is between about 1.5 and 50.0 g/in²/mW and may be betweenabout 5.0 and about 50.0 g/in²/mW. (These preferred Acceptance andReceptivity Under Pressure parameters relate to integrated articleswhich are preferably evaluated as they are intended for use. That is, ifthe article intended for use comprises more than one component or layer,all of the components or layers of the article should be configured asthey would be during normal use when the measurement of theirperformance is made. A more detailed description of the method fordetermining Acceptance Under Pressure performance is included in theTest Methods section, below.)

If the Acceptance Under Pressure performance is too low, more work mustbe done (i.e., more energy input to the system) to cause the viscousfluid bodily waste to penetrate the waste management element 120. Thisis important because the energy available to push the viscous fluidbodily waste into the waste management element 120 is limited and variesfrom wearer to wearer and wearing cycle to wearing cycle. If theReceptivity Under Pressure is too low, more power is required (i.e., agiven amount of energy input is required over a longer period of time)to cause viscous fluid bodily waste to penetrate the waste managementelement 120. This is important because many sources of energy in actualusage conditions are of short duration (e.g., wearer movements).Further, the properties of the viscous fluid bodily waste varyconsiderably between different wearers. Therefore, the absolute amountof viscous fluid bodily waste that will penetrate a structure having ahigh viscous fluid bodily waste penetration per unit work or per unitpower will be greater than the amount that will penetrate a structurehaving a lower acceptance. High acceptance or receptivity values arealso important to the overall performance of an absorbent articlebecause only the portion of a viscous fluid bodily waste discharge thatis accepted can be stored and immobilized.

Once viscous fluid bodily waste has penetrated the waste managementelement 120, it is desirable to store or hold the waste away from thewearer during the remainder of the wearing cycle and away from thecaregiver during the changing process. As used herein, the term “store”refers to the physical separation of material deposited in a diaper fromthe body-facing surface of the article such that the material depositedin the diaper is not immediately in contact with or accessible to thewearer's skin. Storage Under Pressure, or “storage,” is measured as theamount of material held in the structure on a unit area basis, asdescribed in the Test Method Section below. If the Storage UnderPressure capacity is too low, the absolute quantity of viscous fluidbodily waste that can be stored away from skin access per unit area ofthe structure will be reduced. Adequate storage capacity is essential toreduce the probability of leakage and the area of skin contaminated byviscous fluid bodily waste because viscous fluid bodily waste that hasbeen stored is less likely to be available to the body-facing surface ofthe structure for leakage and migration within the article.

In preferred embodiments of the present invention the absorbent articleshould include a waste management element 120 having a Storage UnderPressure value greater than about 0.70 grams per square inch (g/in²) ofthe waste management element 120 of viscous fluid bodily waste. Morepreferably, the waste management element 120 should have a Storage UnderPressure value greater than about 0.80 g/in² of viscous fluid bodilywaste. Even more preferably, the waste management element 120 shouldhave a Storage Under Pressure value greater than about 1.0 g/in² ofviscous fluid bodily waste, and most preferably greater than about 1.2g/in² of viscous fluid bodily waste. Generally, Storage Under Pressurevalues between at least about 0.8 g/in² and about 10.0 g/in², andbetween about 1.0 g/in² and about 10.0 g/in² have been found to beacceptable. (These preferred Storage Under Pressure parameters relate tointegrated articles which are preferably evaluated as they are intendedfor use. Accordingly, all of the components or layers of the articleshould be configured as they would be during normal use when themeasurement of their performance is made. A more detailed description ofthe method for determining Storage Under Pressure performance isincluded in the Test Methods section, below.)

The Storage Under Pressure parameter is different from the Acceptance orReceptivity Under Pressure parameters in that it is an absolute measureof the quantity of viscous fluid bodily waste that can be imbibed withinthe structure on a unit area basis under a given applied pressure.Acceptance or receptivity, on the other hand, is a measure of the amountof material imbibed normalized by the amount of energy that was expendedor power that was input, respectively, to force the material topenetrate the structure. Although each of the numbers is of value byitself, it is the combination of these parameters that gives a moreaccurate picture of the overall performance of a given structure. Forexample, the storage capacity of a structure may not be fully utilizedif the energy required to “fill” the capacity is higher than the energyavailable in a given usage situation. Conversely, the acceptance of astructure may be high (i.e., energy required to penetrate is low), butthe storage capacity may be very low, reducing the overall efficiency ofthe structure. Therefore, it is important to provide structures whichhave both an adequate viscous fluid bodily waste capacity and whichrequire a minimum of energy input (work) or power to fill the availablecapacity. FIG. 11 is a graphical representation of the relationshipbetween Acceptance and Storage Under Pressure values of severalstructures which are described in the Examples below.

Viscous fluid bodily waste that is accepted by, or penetrates, theabsorbent article is preferably also retained in the diaper away fromthe wearer. One preferred way to retain bodily waste, especially viscousfluid bodily waste, is to immobilize the waste in a location away fromthe wearer. As used herein, the term “immobilize” refers to the abilityof the material or structure to retain stored viscous fluid bodily wasteunder an applied pressure and/or the influence of gravitational forces.Immobilization Under Compressed Inversion, or “immobilization,” may beaccomplished by increasing the waste's viscosity (e.g., by dewatering),by mechanical entrapment (i.e., a surface energy phenomenon driven byincreased surface area of contact of the viscous fluid bodily wasteswith the internal regions of the material or structure) or by any othermeans known in the art. “Immobilization Under Compressed Inversion,” asdescribed further in the Test Method Section below, is measured in termsof the percentage of the viscous fluid bodily waste or analog thatremains in the structure after the structure is subjected to an invertedpressure cycle, as described below. “Retention Under,CompressedInversion”, or “retention,” is an absolute measure of how much viscousfluid bodily waste remains “stored” under stressful usage conditions.

Preferably, the waste management element 120 should have a RetentionUnder Compressed Inversion value of greater than about 7.5 g of theviscous fluid bodily waste which penetrates the structure. Morepreferably, the waste management element 120 should have a RetentionUnder Compressed Inversion value of greater than about 8.0 g of viscousfluid bodily waste, and most preferably greater than about 8.5 g ofviscous fluid bodily waste after being subjected to the Retention UnderCompressed Inversion test, as described below. Generally, RetentionUnder Compressed Inversion values between at least about 7.5 g and about100.0 g, and between about 8.0 g and about 100.0 g have been found to beacceptable. Under the same conditions, the waste management element 120should have an Immobilization Under Compressed Inversion value of atleast 70% of the viscous fluid bodily waste accepted by the wastemanagement element 120. More preferably, the waste management element120 should have an Immobilization Under Compressed Inversion value of atleast about 80% and most preferably at least about 85% of the viscousfluid bodily waste accepted by the element 120. Generally,Immobilization Under Compressed Inversion values between at least about70% and about 100%, and between about 80% and about 100% have been foundto be acceptable. (These preferred Immobilization and Retention UnderCompressed Inversion parameters relate to integrated articles which arepreferably evaluated as they are intended for use. Accordingly, all ofthe components or layers of the article should be configured as theywould be during normal use when the measurement of their performance ismade. A more detailed description of the method for determiningImmobilization and Retention Under Compressed Inversion performance isincluded in the Test Methods section, below.)

Without the appropriate immobilization and retention performance, theeffects of improved acceptance and storage performance may be diminishedbecause the viscous fluid bodily waste may return to the body-facingsurface of the structure, increasing the likelihood of leakage orcontamination of the wearer's skin. Further, immobilization is mosteffective if the structure first accepts the waste and then stores it.Viscous fluid bodily waste that is immobilized prior to being storedaway from the wearer's skin may remain on the topsheet in contact withthe skin. Immobilizing viscous fluid bodily waste which is in contactwith the skin can increase the effort required by the caregiver duringthe changing/cleaning process and increases the likelihood of residual,micro-level contamination. “Micro-level contamination” refers to wasteresidue which remains on the skin, but is not easily visible to thehuman naked eye. Therefore, as shown in the graph of FIGS. 9 and 10, itmay be helpful to consider at least three parameters (acceptance,storage, and immobilization or acceptance, storage and retention) for agiven structure when determining its utility for effectively managingviscous fluid bodily wastes.

Although structures which accept, store and immobilize viscous fluidbodily wastes are preferred, in certain embodiments of the presentinvention, the waste management element 120 may comprise only anacceptance element, a storage element or an immobilization element, ormay include a combination of two of the elements, but not the third.Also, in certain embodiments, one element may perform more than onefunction (e.g., a storage element may perform both the storage andimmobilization functions). For example, the absorbent article of thepresent invention may include an acceptance and a storage element tomanage viscous fluid bodily wastes without a separate immobilizationelement, per se. Accordingly, it is desirable to be able to identifysuitable individual acceptance, storage and immobilization elements andto measure their effectiveness separate from an integral absorbentarticle structure. The following discussion identifies several, but notall, suitable acceptance, storage and immobilization elements which canbe used independently of each other or in any combination and apreferred method of determining their relative effectiveness.

Acceptance Element

In a preferred embodiment of the present invention, the waste managementelement 120 includes an acceptance means or acceptance element 150. Theacceptance element 150 is that portion of the diaper 20 which isintended to accept bodily exudates deposited in the diaper 20, and moreparticularly is intended to accept viscous fluid bodily waste. Theacceptance element 150 preferably should have an Acceptance UnderPressure value of greater than 0.70 g/in²/mJ of viscous fluid bodilywaste or an equivalent analog. More preferably, the acceptance element150 should have an Acceptance Under Pressure value of greater than 0.8g/in²/mJ, and most preferably greater than 1.0 g/in²/mJ of viscous fluidbodily waste. Generally, Acceptance Under Pressure values between atleast about 0.6 g/in²/mJ and about 10.0 g/in²/mJ and between about 0.8g/in²/mJ and about 10.0 g/in²/mJ have been found to be acceptable.Alternatively, the acceptance element 150 should have a ReceptivityUnder Pressure of at least about 1.5 grams of viscous fluid bodily wasteper square inch of the acceptance element 150 per milliwatt (mW) ofpower, more preferably greater than about 3.0 g/in²/mW, even morepreferably greater than about 5.0 g/in²/mW, most preferably greater thanabout 10.0 g/in²/mW. Generally, the Receptivity Under Pressure isbetween about 1.5 and 50.0 g/in²/mW and may be between about 5.0 and50.0 g/in²/mW. If the acceptance or receptivity performance is too low,more work must be done, or more power applied, respectively, (i.e., moreenergy input to the system) to cause the viscous fluid bodily waste topenetrate the acceptance element 150. As noted above, high Acceptance orReceptivity Under Pressure performance is important to the overallperformance of an absorbent article because waste which is not acceptedwill stay in contact with the wearer's skin. Further, only the portionof a viscous fluid bodily waste that is accepted can be stored andimmobilized away from the wearer's skin, as contemplated by the presentinvention.

The acceptance element 150 may be any material or structure capable ofaccepting bodily exudates, as described above. The acceptance element150 may include a single material or a number of materials operativelyassociated with each other. Further, the acceptance element 150 may beintegral with another element of the diaper 20 or may be one or moreseparate elements joined directly or indirectly with one or moreelements of the diaper 20. Further, any or all of the acceptance element150 may be removable from the absorbent article for separate disposal,if desirable.

The acceptance element 150 is preferably disposed at least partially inthe crotch region 37 of the diaper 20 adjacent the body surface 47 ofthe core 28, although in some alternate embodiments, the acceptanceelement 150 may include at least a portion of a leg cuff, waistband,fecal waste containment pocket, or the like, or may be operativelyassociated with any such features. Preferably, at least the portion ofthe acceptance element 150 located in the region of diaper 20 which isnear the anus of the wearer during use is unobstructed by overlyinglayers of structures, such as the topsheet 24. Thus, it may be desirableto cut out a portion of the topsheet 24 in the region of the articleintended to be located near the wearer's anus and to provide anacceptance element 150 as the body-side liner in that region.Alternatively, any or all of the topsheet 24 may be made or treated toact as the acceptance element 150. In one embodiment, as shown in FIG.1, the acceptance element 150 includes at least a portion of thetopsheet 24. In other embodiments, the acceptance element 150 mayinclude at least a portion of other elements of the diaper such as theabsorbent core 28 or the storage element (described below).

In some embodiments, it may be desirable to provide the diaper 20 withdifferent acceptance or receptivity performance in different portions ofthe diaper. This may be accomplished by providing different acceptanceelements in the different regions of the diaper 20 or by providing asingle acceptance element 150 which has been manufactured or treated tohave regions of differing acceptance characteristics. Further, theacceptance element 150 may be elevated above the plane of thebody-facing surface of the article so as to be in better control ofexuded viscous fluid bodily wastes. In some embodiments, it may even bedesirable to have the acceptance element 150 in contact with skin ofwearer in proximity of the viscous fluid bodily waste source (e.g., theperianal region).

Suitable materials and structures for use as the acceptance element 150may include apertured nonwoven webs, apertured films, apertured formedfilms, scrims, woven webs, scrim, netting, macroporous thin foams, andthe like. One particularly preferred material is a woven nettingavailable as a Toy Tub Bag from Dollar Tree Dist., of Norfolk, Va.Further, the acceptance element 150, or any portion thereof, may becoated with a lotion or other known substances to add, enhance or changethe performance or other characteristics of the element. For example,the acceptance element 150 may be hydrophobic or hydrophilic or treatedto be either.

Table I shows the Acceptance and Receptivity Under Pressure performanceof several materials. Acceptance and Receptivity Under Pressure data forthe individual acceptance elements shown in Table I is generated via thesame method as Acceptance and Receptivity Under Pressure data for theintegral samples tested below, except that the samples tested for TableI include only the acceptance element 150. Further, the acceptanceelement 150 is tested in conjunction with a standard storage element 147rather than the underlying structure of the absorbent article from whichthe acceptance element 150 was taken. (The standard storage element 147includes a 4 inch square 1.6 millimeter thick aluminum plate having apattern of 153 regularly spaced 4.3 millimeter diameter holes 168, asshown in FIG. 4. The holes are arranged such that there areapproximately 26 holes per square inch.)

TABLE I Acceptance Under Pressure Using a Standard Storage ElementAcceptance Receptivity Under Under Pressure Pressure Acceptance Element(g/in²/mJ) (g/in²/mW) Hydroentangled, apertured nonwoven web 0.45 1.65GH437 from Chicopee Inc., North Charleston, SC Apertured vacuum -formedfilm X-3265 0.16 0.27 from Tredegar Corp. of Terre Haute, IN Wovennetting (Toy Tub Bag) from Dollar 3.54 4.49 Tree Dist., of Norfolk, VA

One parameter in obtaining suitable acceptance and receptivityperformance has been found to be related to the total effective openarea of the acceptance element 150. Preferably, the effective open areaof the acceptance element 150 is at least about 30%, more preferably atleast about 50%, and most preferably at least about 70%. Typically, theeffective open area of the acceptance element 150 should be in the rangeof about 30 to 70%. Such effective open area values and ranges arenecessary to ensure that the waste can easily enter or pass through theacceptance element 150 to the absorbent core, storage element 152 orother underlying structure. This is important because the improvedstorage and/or immobilization characteristics of the present inventionare less likely to be achieved if a sufficient portion of the waste doesnot penetrate the acceptance element 150.

To achieve suitable total effective open area measurements, theacceptance element 150 may include apertures. If the acceptance element150 includes apertures, the apertures preferably have an effectiveaperture size of at least 0.2, square millimeters, more preferably atleast 0.5 square millimeters, even more preferably at least 1.0 squaremillimeters, and most preferably at least 2.0 square millimeters.Generally preferred effective aperture sizes are between about 0.2square millimeters and about 50 square millimeters, and more preferablybetween about 1.0 square millimeters and about 25 square millimeters.Table II shows the total effective open area and the effective open areacontributed by apertures greater than 2.0 square millimeters for anumber of exemplary web-like materials. The Acceptance, Receptivity, andStorage Under Pressure values for each of these materials in conjunctionwith the standard storage element is also shown. These data are alsopresented graphically in FIGS. 19-22. It is readily apparent from thesedata that the above-mentioned ranges for effective open area of theacceptance element are critical for superior waste management elementperformance in terms of immobilization (FIG. 19), storage (FIGS. 20 and22), and acceptance (FIG. 21).

TABLE II Total Effective Open Acceptance Storage Receptivity EffectiveArea from Under Under Under Open apertures > 2.0 Pressure PressurePressure, Example Acceptance Element Description Area, % mm², % g/in2/mJG/in2 g/in2/mW A1 Apertured Vacuum Formed Film 28.5 27.0 1.24 0.56 8.99X5790 (1/8″ honeycomb pattern) from Tredegar, Corp of Terte Haute, IN A2Woven netting Laundry Bag From 63.90 61.0 7.70 1.13 15.27 LBU Inc.,Carlstadt, NJ A3 Woven Netting (Tub Toy Bag) 59.5 38.0 3.7 0.63 8.54from Dollar Tree Norfolk, VA A4 Made from 50 g/m² Corovin LLDPE 23.323.0 1.25 0.39 6.55 with secondary bond sites and ring rolled to producea selectively apertured nonwoven (SAN) as described in U.S. Pat. No.5628097 A5 Standard Acceptance element 150 51.70 0.0 2.95 1.03 6.01 A6 A30 g/m² hydrophobic apertured 20.40 0.0 0.15 0.01 0.24 polypropylenenonwoven produced by Pantex from Pistoia, Italy and identified asPN-S-30 P3 HO A7 A 23.3 g/m² Carded Polypropylene 0.0 0.0 0.10 0.02 0.20nonwoven available as P-8 and produced by Fibertech of Franksville, WI.A8 A 32 g/m² duo-layer phased 19.0 13.0 2.08 0.29 4.14 polypropyleneapertured nonwoven identified as # 97/037 and produced by Amoco Fabrics,Germany

The effective aperture size and percentage open area can be determinedby the procedure described at Col. 10, line 44- Col. 12, line 43 of U.S.Pat. No. 5,342,338 entitled “Disposable Absorbent Article ForLow-Viscosity Fecal Material” issued to Roe on Aug. 30, 1994, which ishereby incorporated by reference herein.

Storage Element

The waste management element 120 of the present invention preferablyalso includes a storage means or storage element 152 capable of storingviscous bodily wastes accepted by the acceptance element 150 or otheroverlying layer(s), if any. In preferred embodiments, the storageelement 152 should have a Storage Under Pressure value of about 0.70g/in² of viscous fluid bodily waste. More preferably, the storageelement 152 should be able to store greater than about 0.80 g/in² ofviscous fluid bodily waste. Even more preferably, the storage element152 should be able to store greater than about 1.0 g/in² of viscousfluid bodily waste, and most preferably greater than about 1.2 g/in² ofviscous fluid bodily waste. Generally, Storage Under Pressure valuesbetween at least about 0.8 g/in² and about 10.0 g/in² and between about1.0 g/in² and about 10.0 g/in² have been found to be acceptable.

The storage element 152 may be located anywhere in the diaper 20.However, it is preferred that the storage element 152 be operativelyassociated with the acceptance element 150 and/or topsheet 24, if any,such that viscous fluid bodily waste accepted by the acceptance element150 may enter the storage element 152. (Embodiments are contemplatedwherein the diaper 20 has no topsheet 24 or acceptance element 150. Insuch cases, the bodily waste may enter the storage element 152 directly,without passing through any overlying structure.) In any case, it ispreferred that the storage element 152 be located in the region of thediaper 20 which is located near the wearer's anus when the diaper 20 isworn. Accordingly, it is preferred that at least a portion of thestorage element 152 be disposed in the crotch region 37 of the absorbentarticle. However, in some alternate embodiments, the storage element 152may include at least a portion of either waist region (as shown in FIGS.5 and 6, for another embodiment 20A of the present invention, in thesecond waist region 38), a leg cuff (as shown in FIG. 6A for theembodiment 20A), the waistband, a fecal waste containment pocket, or thelike, or may be operatively associated with any such features. Further,the storage element 152 may be elevated above the plane of body-facingsurface of the article so as to be in better control of exuded viscousfluid bodily wastes. In some embodiments, it may even be desirable tohave the storage element 152 in contact with skin of wearer in proximityof the viscous fluid bodily waste source (e.g., the perianal region).

The Storage Under Pressure performance of the storage element 152 may beuniform or may vary throughout the diaper 20. Such variations may beaccomplished by employing multiple storage elements 152 in the diaper 20or by providing a single storage element 152 with regions of differentStorage Under Pressure capacities. Further, any or all of the storageelement 152 may be removable from the absorbent article for separatedisposal, if desirable.

The storage element 152 may be any material or structure capable ofstoring bodily exudates, as described above. Thus, the storage element152 may include a single material or a number of materials operativelyassociated with each other. Further, the storage element 152 may beintegral with another element of the diaper 20 or may be one or moreseparate elements joined directly or indirectly with one or moreelements of the diaper 20. In one embodiment, as shown in FIG. 5, thestorage element 152 includes a structure that is separate from the core28. However, embodiments are contemplated wherein the storage element152 includes at least a portion of the core 28.

Suitable materials for use as the storage element 152 may include largecell open foams, macro-porous compression resistant nonwoven highlofts,large size particulate forms of open and closed cell foams (macro and/ormicroporous), highloft nonwovens, polyolefin, polystyrene, polyurethanefoams or particles, structures comprising fibrous looped material, amultiplicity of vertically oriented looped strands of fibers, absorbentcore structures described above having punched holes or depressions, andthe like. (As used herein, the term “microporous” refers to materialswhich are capable of transporting fluids by capillary action. The term“macroporous” refers to materials having pores too large to effectcapillary transport of fluid, generally having pores greater than about0.5 mm in diameter and more specifically, having pores greater thanabout 1.0 mm in diameter.) One embodiment includes a mechanicalfastening loop landing element, having an uncompressed thickness ofabout 1.5 millimeters available as XPL-7124 from the 3M Corporation ofMinneapolis, Minn. Another embodiment includes a 6 denier, crimped andresin-banded nonwoven highloft having a basis weight of 110 grams persquare meter and an uncompressed thickness of 7.9 millimeters which isavailable from the Glit Company of Wrens, Ga. The storage element 152,or any portion thereof, may include or be coated with a lotion or otherknown substances to add, enhance or change the performance or othercharacteristics of the element.

An alternate embodiment of a storage element 152 includes amacro-particulate structure 170 comprising a multiplicity of discreteparticles 172, nonlimiting examples of which are shown as FIGS. 5 and 6.The macro particles 172 preferably have a nominal size, preferablybetween about 1.0 mm and about 25.4 mm, and more preferably betweenabout 2 mm and about 16 mm. However, particles as small as 0.5 mm andsmaller, and particles larger than about 25.4 mm are contemplated.Particles having a nominal size of about 1.0 mm or greater are thosewhich are generally retained on the surface of a U.S. Standard No. 18mesh sieve screen. Particles having a nominal size of less than about25.4 mm are those which generally pass through a U.S. Standard 25.4 mmsieve screen. Particles having a nominal size of 16 mm or greater arethose which are generally retained on the surface of a U.S. Standard No.16 mm sieve screen. The nominal particle size is measured prior toincorporating the particles into a storage element 152 for testing oruse. Particles having a nominal size of 8 mm or greater are those whichare generally retained on the surface of a U.S. Standard 8 mm sievescreen.

The macro-particulate structure 170 may include any number of particles172. Further, the particles 172 may be unjoined and free to move withinthe structure 170 or may be joined to each other by any known means.Alternatively, the structure 170 may include an external support, suchas a meltblown hot-melt glue, a web, a netting, a scrim, a thread orother adhesive or nonadhesive entangling supports. Any of the particles172 may also be joined with any other portion of the diaper structure,such as the topsheet or the core. The particles 172 may also beconstrained in patterned, three-dimensional regions such as pleats,“pillows”, and pockets.

The individual particles 172 may be made from any material suitable foruse in absorbent articles, including the materials described above withregard to the absorbent core 28 or the storage element 152. Thematerials used in the particles 172 may be absorbent, nonabsorbent,microporous, macroporous, resilient, nonresilient, etc. or may have anyother desirable characteristic. Examples of macroporous absorbentmaterials suitable for use in the particles 172 include highloftnonwovens, open cell foams, bundles of fibers, sponges and the like.Other absorbent materials include cellulosic batts, capillary channelfibers, osmotic storage materials such as superabsorbent polymers, etc.Nonabsorbent particles 172 may comprise plastic, metal, ceramic, glass,closed cell foams, column packing materials, synthetic fibers, gels,encapsulated gas, liquids and the like. Further, any or all of theparticles 172 may include odor absorbents, lotions, skin careformulations, antimicrobials, pH buffers, enzyme inhibitors, and thelike.

The storage element 152 may comprise a single type of particle 172(size, shape, material, etc.) or may include a mixture of differentparticles 172. The mixture may be homogeneous; heterogeneous, as whenparticles 172 having different properties are disposed in certain areasof the storage element 152; layered; or any other desirableconfiguration. In some embodiments, more than one type of mixture may beemployed (e.g., macroporous and nonabsorbent particles 172 may behomogeneously mixed in one layer while another layer includes onlyabsorbent particles.) Different layers of particles may be directlyadjacent each other or may be separated by one or more materials, suchas netting, scrim, nonwoven or woven webs, film, foam, adhesive, and thelike.

The macro-particulate structure 170 preferably includes a continuousintersitial void space 174 that is defined by the space between theparticles 172. By varying the size and/or shape of the particles 172,the interstitial void space 174 can be controlled. The particles may beof any known shape, including spheres, oblate spheroids, rectangular andpolygonal solids, and like. Table III shows the void fractions ofparticles having particular alternative shapes and nominal sizes. Othersuitable shapes and void fractions are described in Perry's ChemicalEngineering Handbook, 6th ed., McGraw-Hill, 1984, at p. 18-20.

TABLE III Packing Type Nominal Size (mm) Void Fraction Berl saddles 60.60 13 0.62 6 0.75 Intalox saddles 13 0.78 Pall rings 16 0.87-0.92Raschig rings 6 0.62 13 0.64 19 0.72

Regardless of the makeup of the storage element 152, it should resistcompression so as to maintain some significant level of capacity (e.g.,“storage”) when a compressive force is applied to the storage element152. This property is referred to as the “compressive resistance” of thestorage element. Preferably, the storage element 152 is able to maintainat least about 50% of its original thickness when a compressive force of0.2 psi is applied to the structure (i.e., have a compressive resistanceof at least about 50%). More preferably, the storage element 152 shouldbe able to maintain at least about 70%, even more preferably at leastabout 80%, and most preferably at least 90% of its original thicknesswhen a compressive force of 0.2 psi is applied. Generally, in preferredembodiments, the storage element 152 is able to maintain between about50% and 99% of its original thickness when a compressive force of 0.2psi is applied to the structure. More preferably, the storage element152 should be able to maintain between about 70% and 95% of its originalthickness when a compressive force of 0.2 psi is applied. The storageelement 152 should also be capable of restoring itself to substantiallyits original thickness when the force is removed. This property isreferred to as the “resiliency” of the storage element. Preferably, thestorage element 152 should recover at least about 80% of its originalthickness (i.e., have a resiliency of at least about 80%), and morepreferably at least about 90% of its original thickness after thecompression force of 0.2 psi is removed.

In addition to its storage function, the storage element 152 maytransport viscous fluid bodily waste within the absorbent article 20 indirections generally parallel to the plane of the backsheet 26. Thetransport may be active, such that capillary or other forces result inthe movement of the viscous fluid bodily waste or components thereof(e.g., free water). In other embodiments, the transport may be passivewhereby viscous fluid bodily waste or components thereof move throughthe structure under the influence of externally applied forces, such asgravity, wearer pressure or wearer motion. In the case of passivetransport, the storage element 152 should have relatively large,interconnected channels, or the like, such that the viscous fluid bodilywaste may readily move through the structure with minimum energy input.

Table IV includes Storage Under Pressure performance data relating toseveral individual storage element structures. Storage Under Pressureperformance of individual storage elements 152 may be measured in thesame manner as the Storage Under Pressure test described below withregard to integral structures, except that the individual storageelements 152 are tested separate from any other structure and under astandard acceptance element 150. The standard acceptance element 150 isa stainless-steel wire cloth Type 304 (Standard Grade) 16×16 mesh,available as #9226T45 from McMaster Carr Supply Company of Chicago, Ill.

TABLE IV Storage Under Pressure Using a Standard Acceptance ElementStorage Under Pressure Storage Element (g/in²) Acquisition Layer fromPampers Premium Size 5 Diaper 0.45 from P&G, Cincinnati, OH Loop landingelement of Comparative Example 5 without 0.52 apertured vacuum-formedfilm topsheet Large-cell formed film of Comparative Example 3 without0.70 hydroentangled apertured nonwoven web topsheet Scrubber particlesof Example 3 without woven netting 1.14 topsheet Mixture of scrubberparticles and foam strips of Example 1.80 5 without woven nettingtopsheet Layered assembly of scrubber particles and foam strips of 1.89Example 6 without woven netting topsheet

Improved immobilization performance at lower compressive resistance maybe achieved by including capillary channel fibers in the storage element152. (See Example 16). For example, a storage element 152 may compriseloops of capillary channel fibers (oriented, for example, primarily inthe z-direction) formed by needle-punching the fibers into a substrate.Storage volume is provided by the loop geometry itself However, thecapillary channel fibers, having capillary magnitude grooves on theirexterior, are able to more aggressively retain the feces and/or analogunder applied pressure. Acceptable capillary channel fibers areavailable as six denier/filament fibers identified as Code DPL-77A fromFiber Innovation Technology, Johnson City, Tenn. and are needle-punchedinto a substrate described as DFPN162 and produced by Fiberweb, TerreHaute, Ind. to create a looped, carpet-like structure. However, thestorage element may also include other types of fibers with fecesretention means other than capillary channels as well as non fibrousmembers providing feces retention capacity.

Improved immobilization performance at lower compressive resistance mayalso be achieved by creating layered structures comprising a relativelycompressible top layer (i.e., closer to the wearer) having a macroporousopen structure over a bottom layer (i.e., further from the wearer)comprising a relatively incompressible storage layer capable ofretaining feces and/or analog (e.g., via a multiplicity of fibers, suchas loops, to provide a large contact area). In one suitable embodiment,a macroporous polyurethane/polyester reticulated foam may be used.Preferably the foam should be of uncompressed thickness of between about3 mm and 15 mm, and more preferably between about 4 mm and about 10 mm.The foam preferably has a nominal pore distribution of about 10 poresper inch (ppi). For example, a foam of about 6.3 mm thickness andnominal pore distribution of about 10 pores per inch (ppi) available asSIF/10 from Foamex of Eddystone, Pa., may be placed over a loopstructure comprising a needle punched polypropylene loop carpet/floormat with an uncompressed thickness of about 7 mm produced by RoyalRubber & Manufacturing Co. of South Gate, Calif. may be used. However,any other suitable number or combination of layers may be used includingany of the acceptance and storage elements described herein or othersknown in the art or developed hereafter which provide the desiredperformance characteristics. For example, a macroporous compressiblemember, such as the aforementioned reticulated foam, may be disposedbetween at least a portion of the acceptance element and at least aportion of the fibrous looped material.

Immobilization Element

In addition to or in place of either the acceptance element 150 or thestorage element 152, the waste management element 120 of the presentinvention preferably includes an immobilization means or immobilizationelement 154. The immobilization element 154 should be capable ofimmobilizing and retaining viscous fluid bodily waste that is acceptedand stored by the absorbent article. Preferably, the immobilizationelement 154 should have immobilization values corresponding to at leastabout 70% of the viscous fluid bodily waste accepted by the wastemanagement element 120. More preferably, the immobilization element 154should have immobilization values corresponding to at least about 80%and most preferably at least about 85% of the viscous fluid bodily wasteaccepted by the waste management element 120. Generally, ImmobilizationUnder Compressed Inversion values between at least about 70% and about100% and between about 80% and about 100% have been found to beacceptable. Further, the immobilization element 154 should be capable ofretaining greater than about 7.5 g of viscous fluid bodily waste whichpenetrates the structure. More preferably, the immobilization element154 should be able to retain greater than about 8.0 g of viscous fluidbodily waste, and most preferably greater than about 8.5 g of theviscous fluid bodily waste which penetrates the structure. Generally,Retention Under Compressed Inversion values between at least about 7.5 gand about 100.0 g and between about 8.0 g and about 100.0 g have beenfound to be acceptable.

The immobilization element 154 may be any material or structure capableof reducing the proclivity of viscous fluid bodily waste that haspenetrated the immobilization element 154 from leaving the structure.Thus, the immobilization element 154 may include a single material or anumber of materials operatively associated with each other. Further, theimmobilization element 154 may be integral with another element of thediaper 20 or may be one or more separate elements joined directly orindirectly with one or more elements of the diaper 20. For example, theimmobilization element 154 may be an unjoined layer of material disposedunder the storage element 152 or may include all or a portion of thestorage element 152 which is able to immobilize and retain viscous fluidbodily waste, as described above. In any case, it is preferred that theimmobilization element 154 be operatively associated with the storageelement 152 and the acceptance element 150. This is necessary to ensurethat viscous fluid bodily waste accepted and/or stored by the articlepasses into or comes in contact with the immobilization element 154.Accordingly, it may be desirable to locate the immobilization element154 below the storage element 152 and the acceptance element 150, in atleast a portion of the crotch region 37 of the article. However, asnoted above if the storage element 152 has transportation capabilities,the immobilization element 154 may be located anywhere in the diaper 20such that the viscous fluid bodily waste accepted and/or stored can betransported to the immobilization element 154. Further, as with theacceptance and storage elements 150 and 152, the diaper 20 may haveuniform or nonuniform Immobilization Under Compressed Inversionperformance characteristics. Thus, one or more immobilization elements154 may incorporated in the article having regions of differentimmobilization and/or retention performance. Further, any or all of theimmobilization element 154 may be removable from the absorbent articlefor separate disposal, if desirable.

Suitable materials for use in the immobilization element 154 includemicroporous foams, superabsorbent polymer particles or fibers,cellulosic fibers, capillary channel fibers, entangled synthetic fiberbatts and the like. Some preferred materials include foam absorbentmaterials such as those described in U.S. Pat. Nos. 5,260,345;5,387,207; and 5,650,222. Other preferred materials (include absorbentgelling materials such as those described in U.S. Pat. No. 5,147,345entitled “High Efficiency Absorbent Articles For IncontinenceManagement” issued to Young et al. on Sep. 15, 1992. Each of thesepatents is hereby incorporated by reference herein.

Data on several individual immobilization elements are provided in TableV. The test for Immobilization Under Compressed Inversion performance ofan individual immobilization element 154 is the same as theImmobilization Under Compressed Inversion test method described belowrelating to structures configured as intended for use, except that it isperformed only on the individual storage element 152 and/orimmobilization element 154, and does not include overlying elements suchas topsheets or acceptance elements. Further, the sample is tested withthe standard acceptance element 151 described above. (Analog B, asdescribed below, is used as the test analog.)

TABLE V Immobilization Under Compressed Inversion Using a StandardAcceptance Element Immobilization Storage Under Under CompressedPressure Inversion Storage Element (g/in²) (%) Acquisition Layer fromPAMPERS Premium 0.45 91 Size 5 Diaper available from Procter & Gamble,Cinti., OH Loop landing element of Comparative 0.52 71 Example 5 withoutapertured vacuum-formed film topsheet Large-cell formed film ofComparative 0.70 66 Example 3 without hydroentangled apertured nonwovenweb topsheet Scrubber particles of Example 3 without 1.14 70 wovennetting topsheet Mixture of scrubber particles and foam 1.80 81 stripsof Example 5 without woven netting topsheet Layered assembly of scrubberparticles and 1.89 78 foam strips of Example 6 without woven nettingtopsheet

Preferred Embodiments

As noted above, the present invention is applicable to many types ofabsorbent articles such as diapers, training pants, incontinence briefs,incontinence undergarments or pads, absorbent inserts, diaper holdersand liners, feminine hygiene garments, wipes, disposable mops, bandagesand the like. Thus, the following examples of preferred embodiments ofthe present invention should not construed to limit the scope of theinvention.

One preferred embodiment of the present invention is the absorbentarticle 20A illustrated in FIGS. 5, 6 and/or 6A. The absorbent article20A has a first waist region 36, a second waist region 38 and a crotchregion 37 located between the first waist region 36 and the second waistregion 38. The diaper 20A includes a topsheet 24, a backsheet 26 and anabsorbent core 28 disposed between the topsheet 24 and the backsheet 26.The topsheet 24 is disposed in at least a portion of the first waistregion 36 adjacent the body facing surface 47 of the core 28. The diaper20A also includes an acceptance element 150 joined with the topsheet 24and extending longitudinally away from the topsheet 24 through at leasta portion of the crotch region 37 and at least a portion of the secondwaist region 38. The acceptance element 150 includes a woven nettingavailable as a Tub Toy Bag from Dollar Tree Dist., of Norfolk, Va.

The diaper 20A further includes a storage element 152 located betweenthe acceptance element 150 and the backsheet 26. The storage element 152is located in at least a portion of the crotch region 37 and at least aportion of the second waist region 38. In this embodiment, the storageelement 152 includes a macro-particulate structure 170 comprisingparticles 172. Specifically, the macro-particulate structure 170includes about two grams of the scrubber particles from Example 4,below, mixed with about 0.35 grams of strips of foam absorbent materialhaving a basis weight of 45 grams per square meter, as described in U.S.Pat. No. 5,260,345. The strips have dimensions of about 19 millimetersin length, 6.4 millimeters in width, and 2 millimeters in thickness. Thescrubber particles are distributed over a 2.5 inch×6.4 inch (16 squareinch) area disposed along the longitudinal axis of the article ofapproximately 0.8 mm thick “thin until wet” foam absorbent material(described in U.S. Pat. No. 5,387,207 which is incorporated herein byreference) having a basis weight of 126 grams per square meter. Thescrubber particles are relatively homogeneously mixed with the absorbentfoam strips and are free to move within the area circumscribed by thelayer of “thin-until-wet” absorbent foam material. The particles andstrips are preferably not bonded to the woven netting topsheet or anyother layer. The acceptance element 150 is bonded to the underlyinglayers outside the periphery of the layer of “thin-until-wet” absorbentfoam.

In another embodiment, as shown in FIG. 8, the absorbent article of thepresent invention may be an insert 21 or sanitary napkin which isintended to be applied separately to the wearer or to be placed in thewearer's underwear, an outer cover or the like. Thus, the insert 21 isgenerally not intended to take the form of a pant, but rather is to beused in conjunction with a pant or other structure which holds theinsert 21 in place about the wearer. The absorbent insert 21 has a pairof opposed end regions 135 separated by a central region 137 andincludes an absorbent assembly 27 which may include a backsheet 26, anabsorbent core 28, an acceptance element 150, a storage element 152and/or an immobilization element 154. The insert 21 may also include oneor more attachment element(s) 41 to hold the insert 21 in place in thepant or outer cover 29 during use. The attachment element 41 maycomprise adhesive, cohesive, hooks, snaps, buckles, buttons, ties,magnetic, electronic and/or any other know means for attaching absorbentarticles to undergarments.

TEST METHODS Viscosity

The viscosity may be determined by a controlled stress rheometer. Asuitable rheometer is available from T. A. Instruments, Inc. of NewCastle, Del., as model number SC²100. The rheometer utilizes a stainlesssteel parallel plate fixture. The rheometer has a rigid horizontal firstplate onto which the sample is placed and a second plate mounted overthe first plate such that the axis of said second plate is perpendicularto the first plate. The second plate is 2 or 4 centimeters in diameter.A two centimeter (2 cm) parallel plate is used for firm, pasty, orhighly mucousy samples, while the four centimeter (4 cm) parallel plateis used for very runny or “water-like” fecal samples. The first andsecond plates are spaced apart up to 2000 microns during the measurementprocess. The second plate is connected to a drive shaft for axialrotation. The drive motor and strain sensor are also mounted on thedrive shaft. (Pa) (about 0.017 pounds per square inch) and a test areaof about 20.27 square cm (about 3.142 square inches). If desired, theweight 144 may have a handle 145 to allow it to be easily inserted intoand removed from the cylinder 140. In such cases, the combined mass ofthe handle 145 and the cylindrical weight 144 should equal 24.6 grams.

A sample 146 of the structure to be tested for Acceptance Under Pressureproperties is provided. The sample 146 may be cut from an existingdiaper or may be constructed from material which has not been formedinto a diaper. The sample 146 includes the entire structure intended foruse in an article or the entire structure of the article to beevaluated, including the top layer 161. (In order to measure theAcceptance Under Pressure performance of discrete acceptance elements,as described in the Acceptance Element section above, the AcceptanceUnder Pressure test is performed using the standard storage element 147in place of any underlying structure or layers.) The sample 146 shouldbe cut into a square measuring 10.16 centimeters by 10.16 centimeters(about 4 inches by 4 inches).

Five layers of a high basis weight blotter 149 measuring 4 inches×4inches are provided. The top layer 161 of the sample 146 is removed andthe remaining components, or layers, of the sample 146 (if there aremultiple components or layers) and the five sheets of blotter material149 are weighed to the nearest 0.01 grams. Thus, if the sample 146 isbeing taken from a diaper, the layers of the diaper such as topsheets,secondary topsheets, acquisition layers, absorbent cores etc., should beseparated prior to weighing. (In some cases, a single layer may comprisetwo or more permanently bonded components.) In so doing, care must betaken not to destroy the sample 146 or cause unintended grossdeformation of any parts of the sample 146. The layers of the sample 146may be frozen to aid their separation from adjacent layers of the sample146. Freezing may be accomplished using PH100-15 circuit refrigerantmade by Philips ECG, Inc. of Waltham, Mass.

A suitable sample (typically 2 to 3 grams) of an analog to be tested iscentered on the first plate and generally centered beneath the axis ofthe second plate. Prior to the test, any large pieces of undigested foodmaterial (e.g., seeds) are removed. The first plate is raised intoposition. Excess amounts of the sample which are displaced beyond thediameter of the second plate are removed using a spatula. Water is thenmisted around the edges of the sample to prevent edge effects due tomoisture loss during the measurement process. A programmed applicationof a shear stress, from 50 to 50,000 dynes/cm² for pasty and firmsamples, is applied to the sample by the rheometer. For runny and waterysamples, a shear stress range of 5 to 5000 dynes/cm² was used instead.The data is fitted to a power law function where the apparentviscosity=k j^((n−1)), k=consistency (units of cP×sec^((n−1)), j=shearrate (Units of 1/sec), and n=shear index (dimensionless). Therefore,when j=one 1/sec, the viscosity=k. (The plates are maintained at 35degrees C. throughout the test.)

Acceptance and Receptivity Under Pressure

Acceptance Under Pressure is measured by the following test which usesthe apparatus 139 illustrated in FIG. 2. A hollow plexiglas cylinder 140is provided mounted on a stainless steel plate 142 about 9.5 mm thick.The plate 142 is a square, about 10.16 cm×10.16 cm (about 4 in.×4 in.).The cylinder 140 and plate combination has a height of 7.6 centimeters(about 3.0 inches), an inside diameter of 5.08 centimeters (about 2.00inches) and an outside diameter of 6.3 centimeters (about 2.48 inches).The bottom of the cylinder 140 extends below the plate 142 a distance ofabout 3.5 millimeters. The lip 143 prevents the test fluid 166 fromleaking outside the designated test area. Two 625 gram weights 156 arealso provided, each having a diameter of 5.08 cm (about 2.0 inches).

A cylindrically shaped 24.6 gram plexiglas weight 144 is provided. Theweight 144 has a diameter of 5.08 centimeters (about 2.0 inches), sothat the weight 144 fits with close tolerance within the cylinder 140but can freely slide throughout the hole 141 in the cylinder 140. Thisarrangement provides a pressure of about 119 Pascals

The sample 146 should be reassembled as originally configured on top of5 stacked layers of blotter material 149 with the side of the sample 146intended to face the wearer oriented facing up and away from the blottermaterial 149. The blotter material 149 is preferably filtration gradepaper, available from Ahlstrom Filtration, Inc. of Mt. Holly Springs,Pa. as #632-025, having a basis weight of about 90 grams per meter.

The combined assembly of the sample 146 and the blotter material 149 iscentered on the work surface 164 of a Stevens-Farnell QTS-25 Model7113-5kg Texture Analyzer 160 (available from Leonard Farnell Co. ofHatfield, England), under the probe 162. A suitable probe 162 is a 100cm flat-ended cylindrical aluminum extension rod QTSM3 100 availablefrom the Leonard Farnell Co. of Hatfield England. The cylinder 140 iscentered on the sample 146. The two 625 gram weights 156 are placed onopposite corners (diagonally) of the plate 142 to stabilize it. Asyringe having an opening of about 4 to 6 millimeters is used todispense approximately 10 cubic centimeters of viscous fluid bodilywaste analog 166 (Analog A as described below) through the hole 141 inthe cylinder 140 onto the top of the sample 146.

Viscous fluid bodily waste analog, Analog A, is a fecal material analogmade by mixing 10 grams of CARBOPOL 941 available from the B.F. GoodrichCorporation of Brecksville, Ohio, or an equivalent acrylic polymer in900 milliliters of distilled water. The CARBOPOL 941 and distilled waterare weighed and measured separately. A 3-bladed marine-type propellerhaving a 2 inch diameter paddle, (available from VWR Scientific ProductsCorp. of Cincinnati, Ohio, Catalog # BR4553-64, affixed to a ⅜′ stirringshaft BR4553-52), is used to stir the distilled water. The propellerspeed should be constant at 450 rpm during mixing. The mixer should forma vortex without splashing. The CARBOPOL is slowly sieved into the waterso that it is drawn into the vortex and mixed without forming whiteclumps, or “fish eyes”. The mixture is stirred until all of the CARBOPOLhas been added, and then for a period of 2 minutes thereafter. The sidesof the bowl containing the mixture should be scraped and the bowl shouldbe rotated as needed to achieve a homogeneous mixture. (The mixture willlikely be slightly cloudy with air bubbles). One hundred grams of a 1.0N volumetric NaOH solution, available from J. T. Baker Co.,Phillipsburg, N.J., is then slowly measured into the mixture and themixture is stirred until homogeneous. The mixture should become thickand clear. The mixture should be stirred for 2 minutes after theaddition of the alkali solution. The neutralized mixture should beallowed to equilibrate for at least 12 hours and should be used for theAcceptance Under Pressure test within 96 hours thereafter. Before theCARBOPOL mixture is used, it should be stirred in the container at lowspeed (about 50 rpm) for about 1 minute to ensure the mixture ishomogeneous.

Analog A should, if prepared correctly, have a “hardness” value between55 and 65 grams. Hardness is measured using a Stevens-Farnell QTS-25Texture Analyzer, model 7113-5kg, and associated software on anIntel-based machine having a 486 processor or higher. A ½ inch stainlesssteel spherical probe and an analog receptacle are provided. A suitableprobe is the TA18 probe available from Leonard Farnell Co. of Hatfield,England. The analog receptacle can be made by cutting a 7 milliliterlinear low density polyethylene scintillation vial (having an insidediameter of 0.55 inches +/−0.005 inches) to a 15 millimeter length.Suitable vials are available from Kimble Glass Company of Vineland, N.J.as #58503-7 vials. The analog receptacle is filled to within 2millimeters of the top edge with the analog to be tested. The vial iscentered under the ½ inch spherical stainless steel probe. The probe islowered to a distance of about 1 millimeter from the surface of theanalog in the vial. The probe 162 is moved downward 7 millimeters at 100millimeters per minute and then stopped. The Hardness is the maximumrecorded resistive force encountered by the probe on its 7 millimeterstroke. (The temperature of the room and the analog should be betweenabout 65 to 75 degrees Fahrenheit during the course of the measurement.)

Once the proper amount of viscous fluid bodily waste analog 166, AnalogA, has been measured into the cylinder 140, the 24.6 gram weight 144 isinserted slowly and gently into the hole 140 in the cylinder 140 untilit rests on the surface of the analog. The Texture Analyzer 160 isactivated so the probe 162 depresses the cylindrical weight 144 at arate of 10 millimeters per minute until a resisting force of about 144.6grams is reached. The Texture Analyzer 160 is set to stop the downwardstroke once the resistance force of 144.6 grams is reached. The recorderis set to trigger at a resistive force of 5 grams. (The maximumresisting force of 144.6 grams corresponds to an applied pressure of 700Pascals or 0.1 pounds per square inch). Once a resistive force of 144.6grams is reached, the probe 162 is retracted to its starting position.

The weight 144 is removed from the cylinder 140, and then the cylinder140 is removed from the surface of the sample 146, taking care not todrip any Analog A remaining in the cylinder 140 onto the sample. The toplayer 161 of the sample 146 is then removed from the underlying layer(s)of the sample 146 by dragging the top layer 161 parallel to the surfaceof the underlying layers, if possible. For certain structures where thetop layer 161 is difficult to remove by dragging parallel to theunderlying layers, the top layer 161 may be peeled or lifted away fromthe underlying layers of sample 146. If the sample 146 comprises only asingle layer, the standard acceptance element 151, described below, isutilized as the top layer 161 of the sample 146. The underlying layersof the sample 146 and the blotter material 149 are then weighed. Theamount of test Analog A accepted by the sample 146 equals the increasein combined weight of the underlying layer(s) of the sample 146 and theblotter material 149 caused by the test Analog A penetrating through thetop surface layer of the sample 146 per unit work performed (inmilliJoules) on a unit area basis. The area under the force vs. distancecurve, used in calculating the unit work, is calculated by integratingthe force resisting the probe on its downward stroke over the totaldistance traveled until the maximum force of 144.6 grams is registered.The unit work is calculated using the following equation:

Unit Work (mJ)=Area under the force vs. distance curve (g/mm)(9.81m/s²)/(1000 mm/m)

Receptivity Under Pressure is measure in the same manner as AcceptanceUnder Pressure, as described above, except that the time required toreach the resistive force of 144.6 grams on the downward stroke of theprobe 162 is measured and recorded. Receptivity Under Pressure iscalculated using the following equation: $\begin{matrix}{{Receptivity}\quad {Under}} \\{{Pressure}\quad \left( {g\text{/}{in}^{2}\text{/}{mW}} \right)}\end{matrix} = {\begin{matrix}{{Acceptance}\quad {Under}} \\{{Load}\quad \left( {g\text{/}{in}^{2}\text{/}{mJ}} \right)}\end{matrix} \times \begin{matrix}{{Time}\quad {required}\quad {to}\quad {Reach}} \\{144.6\quad g\quad {Resistive}\quad {force}\quad \left( \sec \right)}\end{matrix}}$

Storage Under Pressure

Storage Under Pressure is measured using the same apparatus 139described above and illustrated in FIG. 2. The hollow cylinder 140,weight 144, and 625 g weights 156 described in the Acceptance UnderPressure test above are provided. A sample 146 of the structure to betested for Storage Under Pressure properties is also provided. Again,the sample 146 may be cut from an existing diaper 20 or may beconstructed from material which has not been formed into a diaper. Thesample 146 should include the entire structure intended for use in anarticle or the entire structure of the article to be evaluated. (Inorder to measure the Storage Under Pressure performance of discretestorage elements, as described in the Storage Element section above, theStorage Under Pressure test is performed using the standard acceptanceelement 150 in place of any overlying structure or layers.) The sample146 should be cut into a square measuring 10.16 centimeters by 10.16centimeters (about 4 inches by 4 inches).

Five layers of a high basis weight blotter 149 (identical to thatdescribed in the Acceptance Under Pressure test above) measuring 4inches×4 inches are provided. The top layer 161 of the sample 149 isremoved and the remaining components, or layers, of the sample 146 (ifthere are multiple components or layers) and the five sheets of blottermaterial 149 are weighed to the nearest 0.01 grams. Thus, if the sample146 is being taken from a diaper, the top layer 161 of the diaper, suchas the topsheet 25, should be separated from the sample 146 prior toweighing. In so doing, care should be taken not to destroy the sample146 or cause unintended gross deformation of the elements of sample 146.The layers of the sample 146 may be frozen, as described above, to aidtheir separation from adjacent layers of the sample 146.

The sample 146 should be reassembled as originally configured on top offive stacked sheets of blotter material 149 with the side intended toface the wearer oriented facing up and away from the blotter material149. The combined assembly of the sample 146 and the blotter material149 is centered on the work surface 164 of the Texture Analyzer 160(described above), under the probe 162. The cylinder 140 is centered onthe sample 146. The two 625 gram weights 156 are placed on diagonallyopposite corners of the plate 142 to stabilize it. A syringe having anopening of about 4 to 6 millimeters is used to dispense 10 cubiccentimeters Analog A (as described above) through the hole in thecylinder 140 onto the top of the sample 146. The 24.6 gram weight 144 isinserted into the hole 141 in the cylinder 140 and the Texture Analyzer160 is activated with the probe 162 depressing the cylindrical weight144 at a rate of 10 millimeters per minute until a resisting force of144.6 grams is reached. (The maximum resisting force of 144.6 gramscorresponds to an applied pressure of 700 Pascals or 0.1 pounds persquare inch). Once the resisting force of 144.6 grams is reached, theprobe 162 is retracted to its starting position.

The weight 144 is removed from the cylinder 140, and then the cylinder140 and weights 156, are removed from the surface of the sample 146,taking care not to drip any Analog A remaining in the cylinder 140 ontothe sample. The sample 146 is then removed from the work surface 164 ofthe Texture Analyzer 160 by dragging the sample 146 parallel to the worksurface 164, if possible. For certain structures where the top layer 161is difficult to remove by dragging parallel to the underlying layers,the top layer 161 may be peeled or lifted away from the underlyinglayers of sample 146. The sample 146 and the blotter 149 are thenweighed. The amount of test Analog A 166 stored equals the increase incombined weight of the underlying layers of the sample 146 and theblotter 149 caused by the test Analog A penetrating into the sample 146on a unit area basis.

Immobilization and Retention Under Compressed Inversion

To measure Immobilization Under Compressed Inversion and Retention UnderCompressed Inversion, a cylinder 140 is mounted on plate 142. Thecylinder 140 has a height of 7.5 centimeters (about 2.95 inches), aninside diameter of 5.08 centimeters (about 2.00 inches) and an outsidediameter of 6.3 centimeters (about 2.48 inches). The hollow cylinder 140and plate 142 are identical to those used in the Acceptance UnderPressure and Storage Under Pressure tests described above, with theexception that the plate does not have the “lip” 143 on the bottom, andthat both the cylinder 140 and the plate 142 are made of stainlesssteel. The stainless steel cylinder 140 and plate 142 have a combinedweight of about 1170 grams.

The sample 146 of the structure to be tested is provided and the toplayer 161, if included in the sample 146, is removed. The remainingunderlying layers of the sample 146 and the five layers of blottermaterial 149 are assembled and weighed. The top layer 161 is then placedon top of this assembly. The sample 146 may also be made from materialsthat have not been made into a structure. The combined assembly of thesample 146 to be tested and blotter 149 is placed on a benchtop 165. (Inorder to measure the Immobilization Under Compressed Inversion andRetention Under Compressed Inversion performance of discreteimmobilization and retention elements, as described in theImmobilization Element section above, the Immobilization UnderCompressed Inversion test is performed using the standard acceptanceelement 150 in place of any top layer 161. All underlying layers areincluded in this evaluation.) A syringe having an opening of about 4 to6 millimeters is used to dispense 10 cubic centimeters of test analogthrough the hole in the cylinder 40 onto the top of the sample 146. Thetest analog (Analog B) used in this measurement is an aqueouspolyacrylamide solution prepared as follows. Twenty-two and five-tenths(22.5 g) grams of polyacrylamide, available from Aldrich ChemicalCompany of Milwaukee, Wis. is mixed with a solution of 20 g of Dawndishwashing solution, available from the Procter & Gamble Company ofCincinnati, Ohio, diluted with 1000 ml distilled water. Mixing is doneusing the same propeller used in mixing Analog A, except that thepropeller speed should be constant during mixing at about 650 rpm.Mixing is done for 30 minutes in a water bath at 180° F. The heatedwater bath is removed and the mixture is stirred for an additional 30minutes. The mixture is allowed to equilibrate for at least 12 hours andused for the Immobilization Under Compressed Inversion test within 96hours. Analog B should have a hardness value (measured as describedabove for Analog A) of between about 7.5 and about 10.5 grams. Analog Bis designed to simulate the water suction power of actual runny fecesfrom breastfed babies. Analog B is generally easier to accept (i.e.,more mobile) than Analog A, which makes its retention more difficult.

The test analog (Analog B) is allowed to penetrate the sample 146 undergravitational force for 3 minutes. The cylinder 140 is then removed fromthe surface of the sample 146 and the entire sample 146 is weighed. Thetop layer 161 of the sample 146 is then removed from the underlyinglayers of the sample 146 by lifting the top layer 161 vertically fromthe surface of the underlying layers and allowing any excess Analog B todrain back into the lower layers. The assembly of the remainder ofsample 146 and the blotter material 149 is then weighed. This provides ameasure of the net quantity of Analog B imbibed by the structure duringthe loading step of this test. The sample 146 is then reassembled,including the top surface layer 161. Three layers of the 4 inch squareblotter material 149 are provided and weighed. A standard storageelement 147 is provided and placed on top of the three layers of blottermaterial 149. The reassembled sample 146 is inverted onto the assemblyof the standard storage element 147 and the three layers of blottermaterial 149. (The standard storage element 147 includes a 4 inch square1.6 millimeter thick aluminum plate having a pattern of 153 regularlyspaced 4.3 millimeter diameter holes 168, as shown in FIG. 4. The holesare arranged such that there are approximately 26 holes per squareinch.)

A 16 pound, 16 square inch weight 158 (corresponding to a 7000 Pascalpressure, or 1.0 psi) is then gently placed on the surface of the sample146 which is facing away from the standard storage element 147. Theweight 158 is removed after three minutes, and the sample 146 isreoriented so that the side insulted by the test Analog B is facing up.The top layer 161 is removed and the weight of the remaining layers ofsample 146 and the five layers of blotter material are measured andrecorded. The sample's Retention Under Compressed Inversion iscalculated as the actual net amount of test Analog B present in theunderlying layers of the structure after the inversion cycle.

Immobilization Under Compressed Inversion is calculated as thepercentage of the test Analog B that penetrated the structure (i.e.,passed through the surface layer into the underlying layers of thesample) during the loading step which remains in the underlying layersof the structure after the inversion step. The equation for determiningImmobilization Under Compressed Inversion is as follows: $\begin{matrix}{{Immobilization}\quad {Under}} \\{{Compressed}\quad {Inversion}}\end{matrix} = {\frac{{{Retention}\quad {Under}\quad {Compressed}\quad {Inversion}\quad (g)}\quad}{\begin{matrix}{{Net}\quad {Quantity}\quad {of}\quad {Analog}\quad B\quad (g)} \\{{imbibed}\quad {during}\quad {loading}\quad {step}}\end{matrix}} \times 100\%}$

Compressive Resistance and Void Volume

The compressive resistance and void volume of storage elements can becalculated from the measurement of the storage element basis weight andcaliper under compression. These physical properties are important tounderstand the maximum absorption capacities at different compressionpressures.

A 2.25 inch diameter circular sample of the structure to be tested ispunched out using a die cutter. The weight of the sample is measuredusing an analytical balance and recorded in grams. The sample basisweight (in grams per square meter) is calculated by dividing the weightof the sample in grams by the surface area of the sample in squaremeters.

With a digital caliper gauge (Model # EG-225 manufactured by Ono Sokkicaliper measurements at 0.09, 0.2, 0.5, 1.0 and then again at 0.09 psiare measured and recorded in sequence. (This gauge has a lip upon whichslotted weights can be mounted. This lip by itself (i.e., with noadditional weights) exerts a baseline force of 0.07 psi when resting onthe sample.) A 30 second waiting period is required between readings. Itis important to note that the same sample should be used to measurecalipers at all compression forces. The sample should also be fixed inone position and all caliper readings should taken at the same locationon the sample. The change from one compression force to another shouldbe done within 5-10 secs by changing out the weights quickly.

At each compression force, void volume and compressive resistance arecalculated as follows:${{Bulk}\quad {Density}\quad \left( {g\text{/}{cc}} \right)} = {\frac{{Weight}\quad {of}\quad {{structure}/{solid}}\quad (g)}{{Total}\quad \left( {{fluid} + {solid}} \right)\quad {volume}}\left( {{Fluid} = {{liquid}\quad {{and}/{or}}\quad {air}}} \right)}$${{Bulk}\quad {Density}\quad \left( {g\text{/}{cc}} \right)} = {\frac{{Basis}\quad {Weight}\quad \left( {g\text{/}m^{2}} \right)}{{Caliper}\quad ({cm})} \times 10^{- 4}}$${{Intrinsic}\quad {density}\quad \left( {g\text{/}{cc}} \right)} = \frac{{Weight}\quad {of}\quad {solid}\quad (g)}{{Volume}\quad {of}\quad {the}\quad {solid}\quad ({cc})}$${Porosity} = \frac{1 - {{Bulk}\quad {density}\quad \left( {g\text{/}{cc}} \right)}}{{Intrinsic}\quad {Density}\quad \left( {g\text{/}{cc}} \right)}$${{Void}\quad {Volume}\quad \left( {{cc}\text{/}g} \right)} = {\frac{1}{{Bulk}\quad {Density}\quad \left( {g\text{/}{cc}} \right)} - \frac{1}{{Intrinsic}\quad {Density}\quad \left( {g\text{/}{cc}} \right)}}$

Compressive Resistance, as used herein, is the ratio of the caliper ofthe structure measured under the 0.2 psi pressure and the caliper at0.07 psi (i.e., the caliper when the unloaded lip of the caliper gaugeis resting on the sample). The equation to calculate CompressiveResistance is shown below. $\begin{matrix}{{Compressive}\quad {Resistance}\quad (\%)} \\{{@\quad 0.2}\quad {psi}}\end{matrix} = {\frac{{Caliper}\quad {at}\quad 0.2\quad {psi}\quad ({cm})}{{Caliper}\quad {at}\quad 0.07\quad {psi}\quad ({cm})}*100}$

Resiliency is the ratio of the caliper of the structure measured at 0.07psi after the entire compression cycle is complete (i.e., after thestructure has been subjected to increasing pressures from 0.07 psithrough 1 psi as described above) and divided by the initial caliper at0.07 psi before the compression loading cycle.${{Resiliency}\quad (\%)} = \frac{{Caliper}\quad {at}\quad 0.07\quad {psi}\quad {after}\quad {the}\quad {complete}\quad {compression}\quad {cycle}\quad \left( {0.07 - {1\quad {psi}}} \right)}{{Caliper}\quad {at}\quad 0.07\quad {psi}\quad {before}\quad {the}\quad {compression}\quad {loading}\quad {cycle}}$

EXAMPLES

Comparative Examples 1-5 are comparative examples of combinationstructures known in art. Examples 1-17 are illustrative embodiments ofthe present invention. Each of the structures was tested as describedabove to determine its capacity to accept, store, immobilize and retainviscous fluid bodily waste. The results are plotted on the graphs shownin FIGS. 9-22.

Comparative Example 1

A four inch by four inch (4 in.×4 in.) sample cut from a Size 1 PAMPERSPremium diaper, available from the Procter & Gamble Co., Cincinnati,Ohio. The sample comprises all the layers of the product and is takenfrom the region containing the rearmost four inches of the absorbentcore. The nonwoven topsheet is separated from the underlying layers forweighing prior to testing as described above. All of the layers areincluded in the actual test.

Comparative Example 2

A four inch by four inch (4 in.×4 in.) sample cut from a Size 1 PAMPERSPremium diaper, available from the Procter & Gamble Co., Cincinnati,Ohio. The sample comprises all the layers of the product and is takenfrom the crotch region area containing the absorbent core. Eightmillimeter diameter holes are punched though the structure of a diaper20B, spaced 13 millimeters on center in staggered rows (see FIG. 7). Thetopsheet is not removed from the structure prior to punching the holes.An apertured vacuum-formed film available as X-3265 from TredegarCorporation of Terre Haute, Ind. is placed over this structure as atopsheet for testing.

Comparative Example 3

A hydroentangled apertured nonwoven web, available as GH437 from theChicopee, Inc. of North Charleston, S.C., is placed over a large-cellvacuum-formed film available from Tredegar Corporation of Terre Haute,Ind. as X5790.

Comparative Example 4

An apertured vacuum-formed film available as X-3265 from TredegarCorporation of Terre Haute, Ind. is placed over a 6 denier polyestercrimped and resin-bonded highloft nonwoven, having a basis weight of 110grams per square meter and an uncompressed thickness of 7.9 millimeters,available from the Glit Company of Wrens, Ga.

Comparative Example 5

An apertured vacuum-formed film available as X-3265 from TredegarCorporation of Terre Haute, Ind. is placed over a mechanical fasteningloop landing element, having an uncompressed thickness of about 1.5millimeters available as XPL-7124 from the 3M Corporation ofMinneapolis, Minn.

Example 1

A woven netting available as a Toy Tub Bag from Dollar Tree Dist., ofNorfolk, Va. is placed over a 6 denier polyester crimped andresin-bonded highloft nonwoven. The nonwoven has a basis weight of 110grams per square meter and an uncompressed thickness of 7.9 millimetersand is available from the Glit Company of Wrens, Ga. The woven nettinghas an effective open area of 60% and primary apertures having aneffective area of 5.0 mm² (as measured by the method incorporated hereinfrom U.S. Pat. No. 5,342,338).

Example 2

A four inch by four inch sample cut from a Size 1 PAMPERS Premiumdiaper, available from the Procter & Gamble Co., Cincinnati, Ohio. Thesample comprises all the layers of the product and is taken from thecrotch region area containing the absorbent core. Eight millimeterdiameter holes are punched though the structure of the diaper 20B,spaced 13 millimeters on center in staggered rows (see FIG. 7). Thetopsheet is not removed from the structure prior to punching the holes.The woven netting described in Example 1, available as a Tub Toy Bagfrom Dollar Tree Dist., of Norfolk, Va., is placed over the structure asa topsheet for testing.

Example 3

The abrasive nonwoven highloft side (referred to hereinafter as the“scrubber” layer) of a scrubbing pad available as Light Duty Scrubbers#00065 from The Libman Company of Arcola, Ill. is separated from thesponge layer. The scrubber layer is approximately seven (7) millimetersthick. This scrubber layer is cut into particles of about 8 mm×7 mm×5 mmand spread loosely on the blotter material 149 in an approximatemonolayer so as to cover an area of 16 square inches with 1.65 grams ofthe scrubber particles. The woven netting described in Example 1,available as a Tub Toy Bag from Dollar Tree Dist., of Norfolk, Va., isplaced over the scrubber particles to form the structure to be tested.

Example 4

Two grams of the scrubber particles as described in Example 3 are mixedwith 0.35 grams of strips of a foam absorbent material having a basisweight of about 45 grams per square meter (as described in U.S. Pat. No.5,260,345 which is incorporated herein by reference). The strips havedimensions of about 19 millimeters in length, 6.4 millimeters in width,and 2 millimeters in thickness. The scrubber particles are distributedover a 16 square inch area of approximately 0.8 mm thick “thin untilwet” foam absorbent material (described in U.S. Pat. No. 5,387,207 whichis incorporated herein by reference) having a basis weight of 126 gramsper square meter. The woven netting described in Example 1, available asa Tub Toy Bag from Dollar Tree Dist., of Norfolk, Va., is placed overthe mixture to form the structure to be tested.

Example 5

1.65 grams of the scrubber particles as described in Example 3 are mixedwith 0.25 grams of strips of the foam absorbent material described inExample 4. The scrubber particles and strips are distributed over a 16square inches of the blotter material 149. The woven netting describedin Example 1, available as a Tub Toy Bag from Dollar Tree Dist., ofNorfolk, Va., is placed over the mixture to form the structure to betested.

Example 6

1.65 grams of the scrubber particles as described in Example 3 islayered over 0.25 grams of the strips of foam absorbent materialdescribed in Example 4 over a 16 square inch area of the blottermaterial 149. The woven netting described in Example 1, available as aTub Toy Bag from Dollar Tree Dist., of Norfolk, Va., is placed over themixture to form the structure to be tested.

Example 7

36.35 grams (about 127 count) of 6 millimeter diameter soda-lime #3000glass balls, available from VWR Scientific Products Corporation ofCincinnati, Ohio as Catalog #26396-621, are mixed with 0.23 grams ofstrips of foam absorbent material described in Example 4, each striphaving length and width dimensions of about 4.5 millimeters. A four inchby four inch (4 in.×4 in.) section of Stay Put Rug Pad, available fromHomemaker, 295 Fifth Street, New York, N.Y. 10016 is modified by placinga 3 inch by 3 inch (3 in.×3 in.), 6.3 millimeter high boundary, madefrom 25.4 millimeter wide 3M SCOTCH Masking Tape onto the pad in orderto stabilize the glass balls for testing. This is in turn placed overthe blotter material 149. The glass ball and foam absorbent materialcube mixture are distributed within the 9 square inch area bound by themasking tape border such that a single layer of the glass beads aremade. The woven netting described in Example 1, available as a Tub ToyBag from Dollar Tree Dist., of Norfolk, Va., is placed over the mixtureto form the structure to be tested.

Example 8

The standard acceptance element 150 is placed over a mechanicalfastening loop landing element, having an uncompressed thickness ofabout 2.1 mm available as XPC-8007 from the 3M Corporation ofMinneapolis, Minn.

Example 9

The standard acceptance element 150 is placed over a high denier, PETresin bonded highloft with an uncompressed thickness of about 1.7 mmavailable as Code 114/046/4 from the Freudenberg Company of Wienheim,Germany.

Example 10

The standard acceptance element 150 is placed over 1.65 grams of the“scrubber” particles, as described in Example 3 above, in place of thewoven netting.

Example 11

The standard acceptance element 150 is placed over a needle punchedpolypropylene loop carpet/floor mat with an uncompressed thickness ofabout 7 mm produced by Royal Rubber & Manufacturing Co. of South Gate,Calif.

Example 12

The standard acceptance element 150 is placed over an open cellPU/polyester reticulated foam of uncompressed thickness of about 6.3 mmthickness and a nominal pore distribution of about 10 pores per inch(ppi) and available as SIF/10 from Foamex of Eddystone, Pa.

Example 13

The standard acceptance element 150 is placed over an open cellpolyurethane/polyester reticulated foam of uncompressed thickness ofabout 6.3 mm thickness and a nominal pore distribution of about 10 poresper inch (ppi) and available as SIF/10 from Foamex of Eddystone, Pa.This combined structure was then placed over a layer of about 0.25 gramsof the strips of foam absorbent material described in Example 4 spreadloosely on the blotter material 149 in an approximate monolayer so as tocover an area of about 16 square inches to form the structure to betested.

Example 14

The standard acceptance element 150 is placed over a layer of about 0.25grams of the strips of foam absorbent material described in Example 4spread loosely in approximate monolayer over the reticulated foamdescribed in Example 13 so as to cover an area of about 16 squareinches. This combined structure is placed over the blotter material 149to form the structure to be tested.

Example 15

The standard acceptance element 150 is placed over a macroporoushumidifier filter eg. Model WF1 of uncompressed thickness of about 6.6mm manufactured by KAZ Inc of Hudson, N.Y.

Example 16

Six denier/filament capillary channel fibers available as Code DPL-77Afrom Fiber Innovation Technology, Johnson City, Tenn. are needle-punchedinto a substrate described as DFPN162 and produced by Fiberweb, TerreHaute, Ind. to create a looped, carpet-like structure having loopdiameters of approximately 8 mm, a basis weight of about 112 g/m2, andan uncompressed caliper of about 2.6 mm. The standard acceptance element150 is placed over this needle-punched element to form the structure tobe tested.

Example 17

The standard acceptance element 150 is placed over a layer of thereticulated foam described in Example 13 above. This combined structurewas placed over the needle punched polypropylene loop carpet describedin Example 11 to form the structure to be tested.

TABLE VI shows the Acceptance, Receptivity, and Storage Under Pressureand Immobilization and Retention Under Compressed Inversion performanceof the structures which are described in Examples C1-C5 and 1-7. Variouscombinations of the data from TABLE V are plotted on the graphsillustrated in FIGS. 9-13.

TABLE VI Retention Acceptance Receptivity Storage Immobilization UnderUnder Under Under Under Compressed Compressed Pressure Pressure PressureInversion Inversion Comparative Examples g/in²/mJ g/in²/mW (g/in²) (%)(g) C1 0.12 0.25 0.03 61 6.0 C2 0.13 0.32 0.05 79 7.4 C3 0.24 1.03 0.4954 5.3 C4 0.01 0.10 0.003 73 7.4 C5 0.40 0.52 0.10 59 5.8 Examples 10.92 5.43 0.77 78 7.7 2 0.84 9.77 1.22 90 9.4 3 1.27 20.72 1.93 73 7.5 41.21 7.93 1.08 91 13.1 5 0.82 11.73 1.37 83 8.5 6 0.71 11.99 1.33 82 8.07 1.18 10.19 1.34 87 8.4

The importance of the combined Acceptance Under Pressure (Acceptance),Storage Under Pressure (Storage), Immobilization Under CompressedInversion (Immobilization), and Retention Under Compressed Inversion(Retention) performance for structures intended to manage viscous fluidbodily waste is readily apparent in the graphs depicted in FIGS. 9-13.In FIGS. 9-10, the structures exemplary of the current art (ComparativeExamples C1-C5) clearly occupy a different region in thethree-dimensional space of Acceptance, Storage, and Immobilization shownin FIG. 9 as compared to the structures exemplary of the presentinvention (Examples 1-7). FIG. 9 shows the difference in Acceptance,Storage and Immobilization efficiency of the structures of the invention(Examples 1-7) in processing viscous fluid bodily waste (e.g., as iscommonly excreted by 100% breastfed infants) versus the structures ofthe current art. This same advantage is also apparent in thethree-dimensional representation of Acceptance, Storage, and Retentionprovided in FIG. 10. The relationship of viscous fluid bodily wasteAcceptance and Storage performance for the Examples (C1-C5 and 1-7) areplotted in the graph in FIG. 11. FIG. 12 depicts the Immobilization andRetention performance of the Examples and FIG. 13 shows the relationshipof Storage and Immobilization of viscous fluid bodily waste. FIG. 14shows the relationship of Storage Under Pressure and Receptivity UnderPressure of viscous fluid bodily waste.

TABLE VII shows the Acceptance, Receptivity, and Storage Under Pressureand Immobilization and Retention Under Compressed Inversion performanceof the structures which are described in Examples 8-17. Variouscombinations of the data from TABLE VII are plotted on the graphsillustrated in FIGS. 15-18.

TABLE VII Compressive Resistance Under Void Volume Storage AcceptanceReceptivity Immobilization Retention 0.2 psi Under 0.2 psi UnderPressure Under Pressure Under Pressure Under Compressed Under CompressedExamples Pressure, % Pressure, cc/in2 g/in2 g/in2/mJ g/in2/mW Inversion,(%) Inversion, g  8 64.00 1.23 0.80 2.53 13.96 76.00 8.43  9 64.00 1.610.61 2.93 10.33 66.00 7.70 10 78.00 3.67 1.14 1.33 10.93 69.90 8.26 1191.00 1.98 0.96 2.51 14.00 99.00 9.98 12 69.00 3.97 0.96 1.69 15.4772.00 7.93 13 93.00 4.41 2.05 2.77 26.60 91.00 9.48 14 93.00 4.41 1.142.02 19.11 89.00 9.53 15 95.00 4.24 2.15 1.30 28.62 94.00 9.60

The importance of the compressive resistance and void volume of thestorage element is readily apparent in the graphs depicted in FIGS. 15,16 and 17. The structures having higher compressive resistance and voidvolume clearly have significantly higher performance in terms of storage(FIGS. 15 and 17) and immobilization (FIG. 16). The improved performancedue to increased compressive resistance can also make possible thinner,reduced caliper articles. Said another way, the caliper of the articlemay be reduced as compressive resistance increases because the voidvolume necessary to store and contain the waste can be maintained undernormal in-use loads.

Examples 16 and 17 of the present invention provide excellentimmobilization with compressive resistance less than 80. The improvedimmobilization is attained by the use of capillary channel fibers formedinto loops (e.g. Example 16) and a reticulated foam placed over a loopmaterial (e.g. Example 17). In such embodiments, the structural elementsand combinations of elements provide immobilization which is clearlydistinct from other articles with similar compressive resistance values.Alternative embodiments including similar or equivalent structuresproviding the improved performance of those described in Examples 16 and17 are considered within the scope of the present invention.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

What is claimed is:
 1. An absorbent article having a first waist region,a second waist region opposed to the first waist region, a crotch regiondisposed between the first waist region and the second waist region, alongitudinal centerline, a lateral centerline, a pair of longitudinaledges and a pair of end edges, the absorbent article further comprising:a topsheet, a backsheet joined with the topsheet; an absorbent coredisposed between at least a portion of the topsheet and the backsheet;an acceptance element having an effective open area of at least about30% and an Acceptance Under Pressure value of greater than about 0.70grams of a viscous fluid bodily waste per square inch of the acceptanceelement per milliJoule of energy input; and a storage element disposedbetween at least a portion of the acceptance element and the backsheet,the storage element having a compressive resistance of at least about70% and a Storage Under Pressure value of greater than about 0.70 gramsof the viscous fluid bodily waste per square inch of the storage elementand the storage element comprising a fibrous looped material and amacroporous compressible member including a macroporouspolyurethane/polyester reticulated foam member, wherein the macroporouscompressible member is disposed between at least a portion of theacceptance element and at least a portion of the fibrous loopedmaterial.
 2. The absorbent article of claim 1 wherein the storageelement has a compressive resistance of at least about 80%.
 3. Theabsorbent article of claim 1 wherein the storage element has acompressive resistance of at least about 90%.
 4. The absorbent articleof claim 1 wherein the acceptance element has an effective open area ofat least about 50%.
 5. The absorbent article of claim 1 wherein theacceptance element has an effective open area of at least about 70%. 6.The absorbent article of claim 1 wherein the storage element furtherincludes a macro-particulate structure comprising a multiplicity ofparticles having a nominal size of between about 1 mm and about 10 mm.7. The absorbent article of claim 6 wherein the particles are absorbent.8. The absorbent article of claim 6 wherein the particles arenon-absorbent.
 9. The absorbent article of claim 1 wherein the fibrouslooped material includes capillary channel fibers.
 10. The absorbentarticle of claim 1 wherein the macroporous polyurethane/polyesterreticulated foam has a nominal pore distribution of about 10 pores perinch.
 11. The absorbent article of claim 10 wherein the macroporouspolyurethane/polyester reticulated foam has an uncompressed thickness ofbetween about 3 mm and about 15 mm.
 12. An absorbent article having afirst waist region, a second waist region opposed to the first waistregion, a crotch region disposed between the first waist region and thesecond waist region, a longitudinal centerline, a lateral centerline, apair of longitudinal edges and a pair of end edges, the absorbentarticle further comprising: a liquid pervious topsheet; a liquidimpervious backsheet joined to the topsheet; an absorbent core disposedbetween at least a portion of the topsheet and the backsheet, and awaste management element disposed in the crotch region having a StorageUnder Pressure value of greater than about 1.00 grams of the viscousfluid bodily waste per square inch of the waste management element andcomprising: an acceptance element having an effective open area of atleast about 30% and an Acceptance Under Pressure value of greater thanabout 0.80 grams of a viscous fluid bodily waste per square inch of theacceptance element per milliJoule of energy input, and a storage elementdisposed between at least a portion of the acceptance element and thebacksheet, the storage element having a compressive resistance of atleast about 70% and a Storage Under Pressure value of greater than about0.70 grams of the viscous fluid bodily waste per square inch of thestorage element and the storage element comprising a fibrous loopedmaterial and a macroporous compressible member including a macroporouspolyurethane/polyester reticulated foam member, wherein the macroporouscompressible member is disposed between at least a portion of theacceptance element and at least a portion of the fibrous loopedmaterial.
 13. The absorbent article of claim 12 wherein the wastemanagement element has an Immobilization Under Compressed Inversionvalue of greater than about 85% of the viscous fluid bodily wasteaccepted by the waste management element.
 14. The absorbent article ofclaim 12 wherein the storage element has a compressive resistance of atleast about 80%.
 15. The absorbent article of claim 12 wherein thestorage element has a compressive resistance of at least about 90%. 16.The absorbent article of claim 12 wherein the acceptance element has aneffective open area of at least about 50%.
 17. The absorbent article ofclaim 12 wherein the acceptance element has an effective open area of atleast about 70%.
 18. The absorbent article of claim 12 wherein thestorage element further includes a macro-particulate structurecomprising a multiplicity of particles having a nominal size of betweenabout 1 mm and about 10 mm.
 19. The absorbent article of claim 18wherein the particles are absorbent or nonabsorbent.
 20. The absorbentarticle of claim 12 wherein the fibrous looped material includescapillary channel fibers.
 21. The absorbent article of claim 12 whereinthe macroporous polyurethane/polyester reticulated foam member has anominal pore distribution of about 10 pores per inch.